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      n[C] a type of fan that transmits power by converting rotational motion into thrust
      The propeller rotates clockwise to propel the ship forward when viewed from astern (right of picture).
      14-ton propeller from Voroshilov, a Kirov-class cruiser on display in Sevastopol
      A marine propeller is sometimes colloquially known as a screw propeller or screw.
      The origin of the screw propeller starts with Archimedes, who used a screw to lift water for irrigation and bailing boats, so famously that it became known as Archimedes' screw.
      The twisted aerofoil shape of modern aircraft propellers was pioneered by the Wright brothers.
      While some earlier engineers had attempted to model air propellers on marine propellers, they realized that a propeller is essentially the same as a wing, and were able to use data from their earlier wind tunnel experiments on wings.
      Propeller dynamics can be modelled by both Bernoulli's principle and Newton's third law.
      n[C] cart or tram
      Among horse-drawn vehicles, a trolley was a goods vehicle with a platform body with four small wheels of equal size, mounted underneath it, the front two on a turntable undercarriage.
      A tram (also known as tramcar; and in North America known as streetcar, trolley or trolley car), is a rail vehicle which runs on tracks along public urban streets (called street running), and also sometimes on separate rights of way.
      A trolleybus (also known as trolley bus, trolley coach, trackless trolley, trackless tram [in early years] or trolley) is an electric bus that draws its electricity from overhead wires (generally suspended from roadside posts) using spring-loaded trolley poles.
      A cart is a vehicle designed for transport, using two wheels and normally pulled by one or a pair of draught animals.
      A handcart is pulled or pushed by one or more people.
      A cart is different from a dray or wagon, which is a heavy transport vehicle with four wheels and typically two or more horses, or a carriage, which is used exclusively for transporting humans.
      A shopping cart (also called a trolley in the UK, and a buggy in some parts of the United States and Canada), is a cart supplied by a shop, especially supermarkets, for use by customers inside the shop for transport of merchandise to the check-out counter during shopping.
      A gurney is a long narrow table with wheels used for moving sick people in a hospital.
      A dolly is a flat frame on wheels used for moving heavy objects.
      The same woman walks over and takes Rachel's laundry cart.
      Every thirty minutes or so the flight attendant would wheel the drinks trolley down the aisle.
      You can catch the number 332 trolley from the train station.
      The waiter was pushing a laden sweet trolley towards our table.
      Passengers with trolleys piled high with luggage waited at the check-in desk.
      The hospital is so overcrowded that some patients are being treated on trolleys in the corridors.
      v[T] act against and reduce the force or effect of sth
      I now know three ways to counteract the effects of tear gas.
      To counteract this, Daisy adds the maximum UV inhibitors to its pool cover material to prolong the life of the product.
      Going for a run or going to the gym doesn't seem to counteract the negative effects of sitting down all day.
      The federal government has tried to counteract this tendency by implementing an official bilingual policy.
      The strong reign of Henry VIII was counteracted by the near disastrous reigns of his son, Edward VI, and his elder daughter, Mary, but his younger daughter, Elizabeth, would be that same symbol of progress that her father was, making the sixteenth century one of the most remarkable eras in England's illustrious history.
      Counter-Strike is a first-person shooter video game developed by Valve Corporation.
      v[I] move with or as if with great speed and a rushing noise
      As the patrol hurried across the dike several grenades hurtled through the air towards them.
      MSL was able to precisely steer itself as it hurtled through the Martian atmosphere.
      Mars Science Laboratory (MSL) is a robotic space probe mission to Mars launched by NASA on November 26, 2011.
      Yeah, terrific. The other astronauts would love to go hurtling through space with a guy named Crash.
      Australia should not hurtle down the track towards a big population.
      The Illinois River has become a warzone as Asian carp - agitated by the sounds of motors - hurtle towards the targets in the boats.
      Travelling on a slick road and with no time to stop, the Porsche hit the car, hurtled into the air and struck two unoccupied vehicles in parking lot near the intersection.
      He took a deep breath, aimed, then fired. The bolt hurtled across the gap between the two buildings and pinned the vampire to the door of the fire exit by the shoulder.
      Compare dash, hurdle, and hurtle.
      n[C] a short piece of music which introduces the main work ¶ action or event that happens before another larger or more important one and forms an introduction to it
      They get into a live-in relationship seeing it as a prelude to marriage, but are not yet fully committed.
      It's a prelude to more American action on the ground.
      This is a prelude for British, and ultimately, US intervention in Syria.
      Plus, adds Martha, having sex without the prelude of kissing, (due to concerns about morning breath), can make the act fun again.
      Harper Lee's To Kill a Mockingbird printed in 1960, served as a prelude to the civil rights advances of the 1960s by portraying race relations from a fresh vantage to the vantage of an innocent child untainted by surrounding racism and bigotry.
      A prelude is a short piece of music, the form of which may vary from piece to piece. The prelude may be thought of as a preface.
      The finale of a show, piece of music, or series of shows is the last part of it or the last one of them.
      n[C] a large city or urban area which is a significant economic, political, and cultural center for a country or region
      A metropolis is a large city or urban area which is a significant economic, political, and cultural center for a country or region, and an important hub for regional or international connections, commerce, and communications.
      The term is Greek and means the "mother city" of a colony (in the ancient sense), that is, the city which sent out settlers.
      For urban centers outside metropolitan areas that generate a similar attraction at smaller scale for their region, the concept of the Regiopolis, short regio, was introduced by German professors in 2006.
      Tokyo is the world's largest metropolis.
      São Paulo is the largest metropolis of the Southern Hemisphere.
      The metropolis, located in northern China, is governed as a direct-controlled municipality under the national government, with 14 urban and suburban districts and two rural counties.
      v[I] create or pass laws
      The Scottish government has said it intends to legislate for both civil and religious marriages for same-sex couples.
      I suspect that any attempt to legislate on the internet will be fiercely opposed.
      Section 92 gives the provinces authority to legislate in matters related to the administration of criminal justice and thereby gives the provincial Attorney General authority to prosecute offences under the Criminal Code.
      To legislate to support the ending of life will be a support to the aspirant manager to end 'bed-blocking' and in areas of mental impairment and will open a Pandora's Box from which lawyers will certainly benefit.
      It was simply just another move to legislate against the LGBT community.
      adj using new methods or achieving new results
      He refused to participate in the groundbreaking ceremony for the nearby Pop Hotel project.
      The element was found because of Sheldon Cooper, and that's groundbreaking.
      His sequel to this groundbreaking book, which anticipated the collapse of the savings-and-loan industry and rewarded readers who followed his recommendations with spectacular returns, came in 1993, with "Crisis Investing for the Rest of the Nineties."
      A groundbreaking new study led by UCLA climate expert Alex Hall shows that climate change will cause temperatures in the Los Angeles region to rise by an average of 4 to 5 degrees Fahrenheit by the middle of this century, tripling the number of extremely hot days in the downtown area and quadrupling the number in the valleys and at high elevations.
      The groundbreaking work of pioneer researcher Dr. Masaru Emoto has dramatically changed the way we look at Earth's most precious resource.
      Compare groundbreaking and groundwork.
      n[C] a unit for measuring area, equal to 10,000 square metres
      In 1795, when the metric system was introduced, the "are" was defined as 100 square metres and the hectare ("hecto-" + "are") was thus 100 "ares".
      An acre is about 0.4047 hectare and one hectare contains about 2.47 acres.
      The current definition of free range allows for a maximum of 1,500 hens per hectare.
      For example, a hectare of cattle pasture in New Zealand will grow grass more prolifically than a hectare of cattle pasture in Jordan, allowing New Zealand to produce more milk in less area.
      The intensity with which agricultural land is farmed has also increased, and with it the burden of soil erosion, water scarcity, nutrient depletion and pollution. In 1987, a hectare of cropland yielded 1.8 tons of produce, but due to intensification this has now risen to 2.5 tons.
      Trafalgar Square has an area of about one hectare.
      Tiananmen Square is the fourth largest city square in the world (880×500 m or 109 acres - 960×550 yd).
      Compare hectare and nectar.
      adj caused by an obsession ¶ extremely interesting, fascinating
      The man is a compulsive liar.
      The above is a true story of a compulsive gambler.
      It's evident that he has a compulsive need to talk.
      Anorexia, bulimia, bingeing and compulsive eating are some of the most common eating disorders.
      Hoarding, Cluttering, and Compulsive Shopping: My Childhood Story
      Did it ever occur to you that not everyone has the compulsive need to sort, organize and label the entire world around them?
      Obsessive–compulsive disorder (OCD) is an anxiety disorder characterized by intrusive thoughts that produce uneasiness, apprehension, fear or worry (obsessions), repetitive behaviors aimed at reducing the associated anxiety (compulsions), or a combination of such obsessions and compulsions.
      Obsessive–compulsive personality disorder (OCPD) is a personality disorder characterized by a pervasive pattern of preoccupation with orderliness, perfectionism, excessive attention to details, mental and interpersonal control, and a need for power over one's environment, at the expense of flexibility, openness, and efficiency.
      Luis Surez's one-man Liverpool rescue mission is compulsive viewing.
      adj deserted or miserable
      v[T] leave a place ruined and deserted ¶ make sb sad and hopeless
      Sunlight is the ultimate source of energy for all living organisms. Without its rays, the earth will be a desolate place.
      He compares the surface of Mars to the vast red-rock deserts of Australia or the American Southwest: stark, desolate, yet eerily beautiful.
      There was a cold wind. Everything was grey and desolate.
      Here I sit lonely and desolate, who so need love and tenderness.
      By the age of 30, she was alone and desolate. In 1868 she commited suicide in a miserable attic in Paris.
      When the doors of the elevator opened she found herself standing in a desolate wasteland covered in garbage and filth.
      The year before his arrival, Dublin had been desolated by a pestilence, and a number of people from Bristol had taken advantage of the decrease in the population to establish themselves there.
      During this period Ulster was also desolated by civil war.
      Compare desolate and isolate.
      n[CU] sth rare
      The argument was that the triple crown is a rarity in baseball, therefore deserving of MVP.
      With luck and further research, hopefully we will see tumours become a rarity in the not too distant future.
      Due to the rarity of the disease and the lack of standard level of care in terms of testing, chronic fatigue (and fibromyalgia, which are often related) can be difficult to diagnose and the person may suffer for months or years before finding the right diagnosis.
      A rarity for streams of this magnitude in Norway, Langfoss remains untapped for hydroelectric production.
      It's no longer a rarity to see and experience an ad that you would actually want to spend time with.
      The Bureau of Indian Affairs is a rarity among federal agencies.
      n[C] a unit for measuring the depth of water
      v[T] work out
      A fathom = 6 feet or 1.8288 metres, is a unit of length in the old imperial and the U.S. customary systems, used especially for measuring the depth of water.
      There are two yards (6 feet) in an imperial fathom.
      Originally based on the distance between a man's outstretched arms, the size of a fathom has varied slightly.
      Samuel Langhorne Clemens (November 30, 1835 – April 21, 1910), better known by his pen name Mark Twain, was an American author and humorist.
      He wrote The Adventures of Tom Sawyer (1876) and its sequel, Adventures of Huckleberry Finn (1885), the latter often called "the Great American Novel".
      Near the completion of Huckleberry Finn, Twain wrote Life on the Mississippi, which is said to have heavily influenced the former book.
      The work recounts Twain's memories and new experiences after a 22-year absence from the Mississippi.
      In it, he also states that "Mark Twain" was the call made when the boat was in safe water – two fathoms.
      Dunham was a private person with depths not easily fathomed.
      Jimmy eventually fathomed it out.
      Compare fathom and phantom.
      n[CU] sleep-like or dreamy state
      Trance denotes any state of awareness or consciousness other than normal waking consciousness.
      Trance states may occur involuntarily and unbidden.
      The Oracle at Delphi was famous for her divinatory trances throughout the ancient Mediterranean world.
      The term trance may be associated with hypnosis, meditation, magic, flow, and prayer.
      Later that night and next day, she still moved in a trance.
      Her live show has had crowds throughout the US and Europe in a trance.
      Some walked around shell-shocked, as if in a trance.
      n[U] a feeling of being calm or peaceful
      Enjoy the serenity of a campfire at your campsite.
      At the age of 50, instead of shrinking into the serenity of success, he continues to march directly into the chaos that is Toronto's nightlife scene.
      It does not take much to disturb the serenity of a cat's world as cats like routine and changes can cause reactions, which are not always to their liking.
      She escaped to the comparative serenity of the bathroom.
      He was able to face death with serenity.
      adj steadfast
      v[T] stanch
      A staunch supporter or believer is very loyal to a person, organization, or set of beliefs, and supports them strongly.
      Last week I met an elderly Sikh gentleman who at one time was a staunch supporter of the Khalistan movement.
      Sir Lawrence Freedman was a foreign policy adviser to Blair and a staunch advocate of the Iraq war.
      I am a staunch defender of police but they are not automatically beyond any criticism.
      The United States has been a staunch ally of Israel and continues to be, although the path has not always been smooth.
      To staunch a wound, or to staunch the blood from a wound, means to stop the wound from bleeding.
      To staunch the flow of something means to stop it.
      Frere hurried to the side of Bates, and lifting him up, strove to staunch the blood that flowed from his chest.
      All efforts to staunch the effects of climate change are not going to work if we do not practice vigorous population control.
      In an attempt to staunch the human tide, Greek coastguard patrols have been equipped with high-speed boats and infrared tracking devices.
      v[IT] lose the right to do or have sth because you have broken a rule
      also an adjective and noun
      You know, according to standard table tennis rules if at any time a player uses his non racket bearing hand to touch the playing surface he or she forfeits the point.
      That trophy is meaningless. I forfeited, therefore you did not win.
      "Are you crazy? We can't go down an empty elevator shaft." "Fine, if you don't want to proceed, then you forfeit the bet, and I'll take possession of your Fantastic Four."
      Look on the bright side. As the result of Penny's forfeit, you have become the world's first winner of "Research Lab."
      Hello? Oh, Chancellor Morton, how are you, sir? Yes, I was expecting your call. I see. Wait. What happens if I choose not to give a speech? Uh-huh. And if I don't want to forfeit the award?
      "Did Leonard send you over here?" "No, we haven't spoken since your abrupt departure last night caused us to forfeit to Stuart and his dastardly ringer Wil Wheaton."
      Those bonuses, earned by people like Bob Diamond should now be forfeit.
      Robert "Bob" Edward Diamond Jr. (born July 27, 1951) is a British-American banker and former group chief executive of the British bank, Barclays Plc.
      v[T] make sth have no effect ¶ deny
      Hey, you can't say you're breezy, that totally negates the breezy.
      The greening efect is negated by the higher consumption.
      We can not negate the role that traditional media companies play in producing what is essentially a public good.
      For those with weak faith I can tell you this does not negate God. There is not a conflict between God and science.
      n[CU] a policy of deficit-cutting, which by definition requires lower spending, higher taxes, or both
      In economics, austerity is the policy of reducing government budget deficits
      Austerity policies may include spending cuts, tax increases, or a mixture of both.
      Austerity may be undertaken to demonstrate the government's fiscal discipline to their creditors and credit rating agencies by bringing revenues closer to expenditures.
      Austerity may also be politically or ideologically driven, or imposed by external agencies.
      In most macroeconomic models, austerity policies generally increase unemployment in the short run.
      Obama sent 10,000 troops to Haiti to "restore order" following the devastating earthquake which killed several hundred thousand people who were living in the slums that were created through World Bank and IMF policies of austerity and structural adjustment.
      An austere way of life is one that is simple and without luxuries (compare spartan).
      n[C] anchored cable or wire nooses set to catch wild animals
      also a verb
      The snare drum is constructed of two heads—both typically made of plastic—along with a rattle of metal wires on the bottom head called the snares.
      The ability to tighten them provides an opportunity to differ the sound of the hit. The strainer is a lever that releases and tightens the snare.
      Snares are anchored cable or wire nooses set to catch wild animals such as squirrels and rabbits.
      Snares are one of the simplest traps and are very effective.
      A snare traps an animal around the neck or the body; a snare consists of a noose made usually by wire or a strong string.
      Snares are widely criticised by animal welfare groups for their cruelty.
      If you describe a situation as a snare, you mean that it is a trap from which it is difficult to escape.
      In my formative years, I was at the perfect age to be snared by video games.
      v[I] (of a cut or wound) become infected and filled with pus
      Regardless, coronary problems are eminently treatable. What's more likely going to kill Howard's mother are the antibiotic-resistant super-bugs festering in every nook and cranny of this hospital.
      If an unpleasant feeling or problem festers, it gets worse because it has not been dealt with.
      Overall, its occupation of Palestinian lands is a festering wound for the whole world.
      This is a festering sore and runs the risk of becoming ugly.
      That would simply allow the problems to fester.
      Yet if we fail to address the values collision, it is likely to fester and become a serious communication breakdown.
      n[UC] a biological process by which an animal physically develops after birth ¶ transformation
      Metamorphosis is a biological process by which an animal physically develops after birth or hatching, involving a conspicuous and relatively abrupt change in the animal's body structure through cell growth and differentiation
      Some insects, fishes, amphibians, molluscs, crustaceans, cnidarians, echinoderms and tunicates undergo metamorphosis, which is usually accompanied by a change of habitat or behavior.
      He talked about the economy, PC sales, the advance of silicon and the metamorphosis of netbooks at a morning session of the Web 2.0 Summit in San Francisco today.
      I don't think it's completely obsolete and the metamorphosis of the industry has not yet been completed.
      It's a revolution, a transformation, a sort of metamorphosis.
      If one thing morphs into another thing, especially something very different, the first thing changes into the second.
      n[sC] chest or breast
      Renaissance fairs aren't about historical accuracy. They're about taking chubby girls who work at Kinko's and lacing them up in corsets so tight their bosom jumps out and says "Howdy."
      That should display enough of your bosom to attract a new mate, or a hungry infant.
      How do you feel about concealing a recording device in the cleavage of your ample bosom?
      Knowledge of physics and a bosom that defies it. You're the whole package, aren't you?
      "Can I help you to find anything?" "A comic that depicts a woman whose bosom can't be used as a flotation device."
      I'll eat later. Right now, I'm suckling at the informative bosom of mother physics.
      You're all wasting your time. Sheldon is the most qualified for the job, and no amount of gravity-defying bosom's going to change that.
      Compare boob, bosom, and breast.
      A bosom friend is a friend who you know very well and like very much indeed.
      He breathed his last, died in the arms of his bosom friend.
      The bosom of something is the loving care and protection of it.
      The Sacred Garden represented being within the bosom of our Creator - protected - looked after and watched over.
      The breast is the upper ventral region of the torso of a primate, in left and right sides, containing the mammary gland which in a female can secrete milk used to feed infants.
      Both men and women develop breasts from the same embryological tissues.
      However, at puberty, female sex hormones, mainly estrogen, promote breast development which does not occur in men due to the higher amount of testosterone.
      As a result, women's breasts become far more prominent than those of men.
      adj fake
      v[T] fake
      If it does not, or if it is missing, the card may be counterfeit.
      During fiscal year 2005, the Secret Service seized over $113 million in counterfeit U.S. currency.
      The book's next chapter discusses the market for counterfeit goods.
      To comply, Chinese companies will have to change their long-time practice of relying on counterfeit products.
      Currently, there are more sanctions around the use of illegal tobacco than counterfeit drugs.
      The company may record your name and ID number to prevent fraud and counterfeiting.
      n[U] a feeling of excitement or anxiety when you do not know what will happen next
      Suspense is a feeling of pleasurable fascination and excitement mixed with apprehension, tension, and anxiety developed from an unpredictable, mysterious, and rousing source of entertainment.
      In thrillers, suspense is the key element authors use to leave the reader or viewer hanging, trying to figure out what will happen next.
      A cliffhanger or cliffhanger ending is a plot device in fiction which features a main character in a precarious or difficult dilemma, or confronted with a shocking revelation at the end of an episode of serialized fiction.
      The book is a masterly exercise in the orchestration of tension and suspense.
      This movie is full of suspense and appeals to a wide audience, even my mum loved it.
      It's so good at building up the suspense and drawing you in.
      The action scenes were absolutely fantastic, and they keep you in suspense.
      If you keep or leave someone in suspense, you deliberately delay telling them something that they are very eager to know about.
      But she gave no indication of her answer, leaving Mr Todd in suspense.
      Cast of Shadows is a 2005 suspense novel by the American writer Kevin Guilfoile.
      Compare suspend, suspense, and suspension.