[under false colors] See: SAIL UNDER FALSE COLORS.
[under fire]{adv. phr.} Being shot at or being attacked; hit by attacks or accusations; under attack. •/The soldiers stood firm under fire of the enemy./ •/The principal was under fire for not sending the boys home who stole the car./
[under lock and key]{adv. phr.} Secured; locked up; well protected. •/Dad keeps all his valuables under lock and key./
[under one’s belt]{adv. phr.}, {informal} 1. In your stomach; eaten; or absorbed. •/Once he had a good meal under his belt, the man loosened his tie and fell asleep./ •/Jones is talkative when he has a few drinks under his belt./ 2. In your experience, memory or possession; learned or gotten successfully; gained by effort and skill. •/Jim has to get a lot of algebra under his belt before the examination./ •/With three straight victories under their belts, the team went on to win the championship./
[under one’s breath]{adv. phr.} In a whisper; with a low voice. •/The teacher heard the boy say something under his breath and she asked him to repeat it aloud./ •/I told Lucy the news under my breath, but Joyce overheard me./
[under one’s hat] See: KEEP UNDER ONE’S HAT.
[under one’s heel]{adv. phr.} In one’s power or control. •/If one marriage partner always wants to keep the other person under his or her heel, it is not a happy or democratic arrangement and may lead to a divorce./
[under one’s nose] or [under the nose of] {adv. phr.}, {informal} In sight of; in an easily seen or noticeable place. •/The thief walked out of the museum with the painting, right under the nose of the guards./ •/When Jim gave up trying to find a pen, he saw three right under his nose on the desk./
[under one’s own steam]{adv. phr.}, {informal} By one’s own efforts; without help. •/The boys got to Boston under their own steam and took a bus the rest of the way./ •/We didn’t think he could do it, but Bobby finished his homework under his own steam./
[under one’s skin] See: GET UNDER ONE’S SKIN.
[under one’s spell]{adv. phr.} Unable to resist one’s influence. •/From the first moment they saw each other, Peter was under Nancy’s spell./
[under one’s thumb] or [under the thumb] {adj.} or {adv. phr.} Obedient to you; controlled by you; under your power. •/The Jones family is under the thumb of the mother./ •/Jack is a bully. He keeps all the younger children under his thumb./ •/The mayor is so popular that he has the whole town under his thumb./ Compare: JUMP THROUGH THE HOOP.
[under one’s wing]{adv. phr.} Under the care or protection of. •/Helen took the new puppy under her wing./ •/The boys stopped teasing the new student when Bill took him under his wing./ Compare: IN TOW.
[under orders]{adv. phr.} Not out of one’s own desire or one’s own free will; obligatorily; not freely. •/"So you were a Nazi prison guard? " the judge asked. "Yes, your Honor," the man answered, "but I was acting under orders and not because I wished to harm anyone."/
[under pain of] See: ON PAIN OF also UNDER PAIN OF.
[under protest]{adv. phr.} Against one’s wish; unwillingly. •/"I’ll go with you all right," she said to the kidnapper, "but I want it clearly understood that I do so under protest."/
[understand] See: GIVE ONE TO UNDERSTAND.
[under the circumstances] also [in the circumstances] {adv. phr.} In the existing situation; in the present condition; as things are. •/In the circumstances, Father couldn’t risk giving up his job./ •/Under the circumstances, the stagecoach passengers had to give the robbers their money./
[under the collar] See: HOT UNDER THE COLLAR.
[under the counter]{adv. phr.}, {informal} Secretly (bought or sold). •/That book has been banned, but there is one place you can get it under the counter./ •/The liquor dealer was arrested for selling beer under the counter to teenagers./ — Also used like an adjective, with hyphens. •/During World War II, some stores kept scarce things hidden for under-the-counter-sales to good customers./
[under the hammer]{adv. phr.} Up for sale at auction. •/The Brights auctioned off the entire contents of their home. Mrs. Bright cried when her pewter collection went under the hammer./ •/The picture I wanted to bid on came under the hammer soon after I arrived./
[under the nose of] See: UNDER ONE’S NOSE.
[under the sun]{adj.} or {adv. phr.} On earth; in the world. — Used for emphasis. •/The President’s assassination shocked everyone under the sun./ •/Where under the sun could I have put my purse?/
[under the table] See: UNDER THE COUNTER.
[under the thumb of] See: UNDER ONE’S THUMB.
[under the weather]{adv. phr.} In bad health or low spirits. •/Mary called in today asking for a sick day as she is under the weather./
[under the wire]{adv. phr.} With a narrow time limit; in the last minute. •/The journalist’s new lead article on Russia was due in press at 5 P.M., and he got it in at 4:57, just under the wire./
[underway]{adv. phr.} In progress; in motion. •/The yearly fund-raising campaign for the renovation of our university campus is already underway./
[under wraps]{adv.} or {adj. phr.} Not allowed to be seen until the right time; not allowed to act or speak freely; in secrecy; hidden. — Usually used with "keep". •/We have a new player, hut we are keeping him under wraps until the game./ •/What the President is planning will be kept under wraps until tomorrow./ •/The spy was kept under wraps and not allowed to talk to newspapermen./ Compare: UNDER COVER.
[unknown quantity]{n.} Someone or something whose value and importance are not known, especially in a certain situation, time or place; a new and untested person or thing. •/What we would find if we could fly to the moon is an unknown quantity./ •/The new player is still an unknown quantity. We’ll find out how good he is in the game./