Definition of "fail" in English

verb

1. (intransitive) To be unsuccessful.

   • Throughout my life, I have always failed.

2. (transitive) Not to achieve a particular stated goal. (Usage note: The direct object of this word is usually an infinitive.)

   • The truck failed to start.

3. (transitive) To neglect.

   • The report fails to take into account all the mitigating factors.

4. (intransitive) Of a machine, etc.: to cease to operate correctly.

   • After running five minutes, the engine failed.

5. (transitive) To be wanting to, to be insufficient for, to disappoint, to desert; to disappoint one's expectations.

   • I've failed my parents many times growing up.

6. (ambitransitive) To receive one or more non-passing grades in academic pursuits.

   • I failed English last year.

7. (transitive) To give a student a non-passing grade in an academic endeavour.

   • The professor failed me because I did not complete any of the course assignments.

8. (transitive, obsolete) To miss attaining; to lose.

9. To be wanting; to fall short; to be or become deficient in any measure or degree up to total absence.

   • The crops failed last year.

10. (archaic) To be affected with want; to come short; to lack; to be deficient or unprovided; used with of.

11. (archaic) To fall away; to become diminished; to decline; to decay; to sink.

12. (archaic) To deteriorate in respect to vigour, activity, resources, etc.; to become weaker.

    • A sick man fails.

13. (obsolete) To perish; to die; used of a person.

14. (obsolete) To err in judgment; to be mistaken.

15. To become unable to meet one's engagements; especially, to be unable to pay one's debts or discharge one's business obligation; to become bankrupt or insolvent.

noun

1. A failure, especially of a financial transaction (a termination of an action).

2. A failing grade in an academic examination.

3. (slang, US) A failure (something incapable of success).

4. (uncountable, slang) Poor quality; substandard workmanship.

   • The project was full of fail.

adjective

1. (slang, US) Unsuccessful; inadequate; unacceptable in some way.