The verb fail describes something that stops working, like brakes in a car that fail, or is found to be unacceptable, like restaurants that fail their inspection for cleanliness.

The verb fail comes from the Old French word faillir, meaning “be lacking,” “miss,” or “not succeed.” You can fail an exam, which means you didn't get at least a minimum number of points to pass. You can fail to live up to your potential, meaning you aren't able to meet expectations. When businesses fail, it means financial problems force them to close.

Definitions of fail
  1. verb
    be unable
    “I fail to understand your motives”
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    bring off, carry off, manage, negociate, pull off
    be successful; achieve a goal
  2. verb
    fail to do something; leave something undone
    “She failed to notice that her child was no longer in his crib”
    “The secretary failed to call the customer and the company lost the account”
    synonyms: neglect
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    lose track
    fail to keep informed or aware
    strike out
    put out or be put out by a strikeout
    default, default on
    fail to pay up
    fail to perform adequately due to tension or agitation
    fail to catch, as of a ball
    fail to attend an event or activity
    strike out (a batter), (of a pitcher)
    strike out by swinging and missing the pitch charged as the third
    cut, skip
    intentionally fail to attend
  3. verb
    fall short in what is expected
    “She failed in her obligations as a good daughter-in-law”
    “We must not fail his obligation to the victims of the Holocaust”
    bomb, flunk, flush it
    fail to get a passing grade
  4. verb
    judge unacceptable
    “The teacher failed six students”
    bomb, flunk, flush it
    fail to get a passing grade
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    accept or judge as acceptable
    type of:
    evaluate, judge, pass judgment
    form a critical opinion of
  5. verb
    fail to get a passing grade
    “She studied hard but failed nevertheless”
    “Did I fail the test?”
    synonyms: bomb, flunk, flush it
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    make it, pass
    go successfully through a test or a selection process
  6. verb
    stop operating or functioning
    “The engine failed on the way to town”
    synonyms: break, break down, conk out, die, give out, give way, go, go bad
    render inoperable or ineffective
    buy the farm, cash in one's chips, choke, conk, croak, decease, die, drop dead, exit, expire, give-up the ghost, go, kick the bucket, pass, pass away, perish, pop off, snuff it
    pass from physical life and lose all bodily attributes and functions necessary to sustain life
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    crash, go down
    stop operating
    blow, blow out, burn out
    melt, break, or become otherwise unusable
    fail to fire or detonate
    malfunction, misfunction
    fail to function or function improperly
    get stuck and immobilized
    type of:
    undergo a change; become different in essence; losing one's or its original nature
  7. verb
    be unsuccessful
    “Where do today's public schools fail?”
    “The attempt to rescue the hostages failed miserably”
    synonyms: go wrong, miscarry
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    bring home the bacon, come through, deliver the goods, succeed, win
    attain success or reach a desired goal
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    take it on the chin
    undergo failure or defeat
    fail to reach or get to
    fail by aiming too high or trying too hard
    ball up, blow, bobble, bodge, bollix, bollix up, botch, botch up, bumble, bungle, butcher, flub, fluff, foul up, fumble, louse up, mess up, mishandle, muck up, muff, screw up, spoil
    make a mess of, destroy or ruin
    strike out
    be unsuccessful in an endeavor
    suffer defeat, failure, or ruin
    suffer failure, as in some enterprise
    fall flat, fall through, flop, founder
    fail utterly; collapse
    fail to progress or succeed
  8. verb
    prove insufficient
    “The water supply for the town failed after a long drought”
    synonyms: give out, run out
  9. verb
    become bankrupt or insolvent; fail financially and close
    “A number of banks failed that year”
  10. verb
    disappoint, prove undependable to; abandon, forsake
    “His sense of smell failed him this time”
    “His strength finally failed him”
    “His children failed him in the crisis”
    synonyms: betray
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    type of:
    disappoint, let down
    fail to meet the hopes or expectations of
  11. verb
    get worse
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    type of:
    decline, worsen
    grow worse
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