fail

verb

• 1be unsuccessful in achieving one’s goal:he failed in his attempt to secure election [with infinitive]:they failed to be ranked in the top ten
• [with object] be unsuccessful in (an examination, test, or interview):she failed her finals
• [with object] (of a person or a commodity) be unable to meet the standards set by (a test of quality or eligibility):the player has failed a drug test
• [with object] judge (someone, especially in an examination) not to have passed.

• 2neglect to do something: [with infinitive]:the firm failed to give adequate risk warnings
• [with infinitive] behave in a way contrary to hopes or expectations by not doing something:commuter chaos has again failed to materialize
• (cannot fail to be/do something) used to express a strong belief that something must be the case:you cannot fail to be deeply impressed
• (never fail to do something) used to indicate that something invariably happens:such comments never failed to annoy him
• [with object] desert or let down (someone):at the last moment her nerve failed her

• 3break down; cease to work well:a truck whose brakes had failed
• become weaker or of poorer quality; die away:the light began to fail (as adjective failing)his failing health
• (especially of a rain or a crop or supply) be lacking or insufficient when needed or expected.
• (of a business or a person) be obliged to cease trading because of lack of funds; become bankrupt.

noun

• a grade that is not high enough to pass an examination or test.