lose

American Heritage® Dictionary of the English Language, Fourth Edition

1. v. To be unsuccessful in retaining possession of; mislay: He's always losing his car keys.
2. v. To be deprived of (something one has had): lost her art collection in the fire; lost her job.
3. v. To be left alone or desolate because of the death of: lost his wife.
4. v. To be unable to keep alive: a doctor who has lost very few patients.
5. v. To be unable to keep control or allegiance of: lost his temper at the meeting; is losing supporters by changing his mind.
6. v. To fail to win; fail in: lost the game; lost the court case.
7. v. To fail to use or take advantage of: Don't lose a chance to improve your position.
8. v. To fail to hear, see, or understand: We lost the plane in the fog. I lost her when she started speaking about thermodynamics.
9. v. To let (oneself) become unable to find the way.
10. v. To remove (oneself), as from everyday reality into a fantasy world.
11. v. To rid oneself of: lost five pounds.
12. v. To consume aimlessly; waste: lost a week in idle occupations.
13. v. To wander from or become ignorant of: lose one's way.
14. v. To elude or outdistance: lost their pursuers.
15. v. To be outdistanced by: chased the thieves but lost them.
16. v. To become slow by (a specified amount of time). Used of a timepiece.
17. v. To cause or result in the loss of: Failure to reply to the advertisement lost her the job.
18. v. To cause to be destroyed. Usually used in the passive: Both planes were lost in the crash.
19. v. To cause to be damned.
20. v. To suffer loss.
21. v. To be defeated.
22. v. To operate or run slow. Used of a timepiece.
23. lose out To fail to achieve or receive an expected gain.
24. idiom. lose it Slang To lose control; blow up.
25. idiom. lose it Slang To become deranged or mentally disturbed.
26. idiom. lose it Slang To become less capable or proficient; decline.
27. idiom. lose out on To miss (an opportunity, for example).
28. idiom. lose time To operate too slowly. Used of a timepiece.
29. idiom. lose time To delay advancement.

Century Dictionary and Cyclopedia

1. To miss from present possession or knowledge; part with or be parted from by misadventure; fail to keep, as something that one owns, or is in charge of or concerned for, or would keep.
2. To be dispossessed, deprived, or bereaved of; be prevented or debarred from keeping, holding, or retaining; be parted from without wish or consent: as, to lose money by speculation; to lose blood by a wound; to lose one's hair by sickness; to lose a friend by death.
3. To cease to have; part with through change of condition or relations; be rid of or disengaged from.
4. To fail to preserve or maintain: as, to lose one's reputation or reason; to lose credit.
5. To fail to gain or win; fail to grasp or secure; miss; let slip: as, to lose an opportunity; to lose a prize, a game, or a battle.
6. To let slip or escape from observation, perception, etc.: as, I lost what he was saying, from inattention; we lost the ship in the fog.
7. To fail to profit by; miss the use, advantage, or enjoyment of; waste.
8. To cause to miss or be deprived of; subject to the loss of: as, his slowness lost him the chance.
9. To displace, dislodge, or expel.
10. To give over to ruin, disgrace, or shame: chiefly in the past participle.
11. To be bewildered; have the thoughts or reason hopelessly perplexed or confused.
12. To become abstracted or fall into a reverie; become absorbed in thought; lose consciousness, as in slumber.
13. To suffer loss or deprivation.
14. To incur forfeit in a contest; fail to win.
15. To succumb; fail; suffer by comparison.
16. n. The act of losing; loss.
17. A Middle English form of loose.
18. n. Praise; fame; reputation; credit.
19. n. Report; news; gossip.
20. To praise.

Wiktionary

1. v. transitive To cause (something) to cease to be in one's possession or capability due to unfortunate or unknown circumstances, events or reasons.
2. v. transitive To have (an organ) removed from one's body, especially by accident.
3. v. transitive To fail to win (a game, competition, trial, etc).
4. v. transitive To shed (weight); to reduce.
5. v. transitive To experience the death of (someone to whom one has an attachment, such as a relative or friend).
6. v. transitive To be unable to follow or trace (somebody or something) any longer.
7. v. transitive, informal To shed, remove, discard, or eliminate.
8. v. Of a clock, to run slower than expected.
9. v. To cause (someone) the loss of something; to deprive of.

GNU Webster's 1913

1. v. To part with unintentionally or unwillingly, as by accident, misfortune, negligence, penalty, forfeit, etc.; to be deprived of
2. v. To cease to have; to possess no longer; to suffer diminution of
3. v. Not to employ; to employ ineffectually; to throw away; to waste; to squander
4. v. To wander from; to miss, so as not to be able to and; to go astray from.
5. v. To ruin; to destroy; as destroy.
6. v. To be deprived of the view of; to cease to see or know the whereabouts of.
7. v. To fail to obtain or enjoy; to fail to gain or win; hence, to fail to catch with the mind or senses; to miss.
8. v. rare To cause to part with; to deprive of.
9. v. To prevent from gaining or obtaining.
10. v. To suffer loss, disadvantage, or defeat; to be worse off, esp. as the result of any kind of contest.

WordNet 3.0

1. v. place (something) where one cannot find it again
2. v. fail to keep or to maintain; cease to have, either physically or in an abstract sense
3. v. retreat.
4. v. fail to make money in a business; make a loss or fail to profit
5. v. miss from one's possessions; lose sight of
6. v. fail to perceive or to catch with the senses or the mind
7. v. fail to get or obtain
8. v. suffer the loss of a person through death or removal
9. v. fail to win
10. v. allow to go out of sight
11. v. be set at a disadvantage