v. failed, fail·ing, fails
1. To prove deficient or lacking; perform ineffectively or inadequately: failed to fulfill their promises; failed in their attempt to reach the summit.
2. To be unsuccessful: an experiment that failed.
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 patient's heart 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 . . . hold . . . those horrors up to the light of justice. Otherwise we would fail our inescapable obligation to the victims of Nazism: to remember" Anthony Lewis.