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fail

(fāl)

v. failed, fail·ing, fails

v.intr.

1. To prove deficient or lacking; perform ineffectively or inadequately: failed to fulfill their promises; failed in their attempt to reach the summit.

a. To be unsuccessful: an experiment that failed.

b. To be unsuccessful in being acted upon: an idea that failed to be accepted by the board.

3. To receive an academic grade below the acceptable minimum.

4. To prove insufficient in quantity or duration; give out: The water supply failed during the drought.

5. To decline, as in strength or effectiveness: The light began to fail.

6. To cease functioning properly: The engine failed.

7. To give way or be made otherwise useless as a result of excessive strain: The rusted girders failed and caused the bridge to collapse.

8. To become bankrupt or insolvent: Their business failed during the last recession.

v.tr.

1. To disappoint or prove undependable to: Our sentries failed us.

2. To abandon; forsake: His strength failed him.

3. To omit to perform (an expected duty, for example): We must not fail our obligation to the earthquake victims.

4. To leave undone; neglect: failed to wash the dishes.

a. To receive an academic grade below the acceptable minimum in (a course, for example): failed algebra twice.

b. To give such a grade of failure to (a student): failed me in algebra.

6. To be detected by (a drug test) as having used a banned substance.

1. A failing grade: The student received a fail on the final paper.

2. Informal Something that does not achieve the desired result; a failure: My first attempt to make flourless cookies was a big fail.

Idiom:

without fail

1. With no chance of failure: Be here at noon without fail.

2. Every single time: "Always we get a good rain on Labor Day, without fail—like clockwork" (Rick Bass)."Whenever he returned to his hut, almost without fail some money was missing from the basket" (Paul Theroux).

[Middle English failen, from Old French faillir, from Vulgar Latin *fallīre, variant of Latin fallere, to deceive.]

Indo-European & Semitic Roots Appendices

Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:

Indo-European Roots

Semitic Roots

The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.

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Indo-European & Semitic Roots Appendices

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