English definition of “fail”
NOT SUCCEED [I] › to not be successful: Dad's business failed after just three years. She keeps failing in her attempt to lose weight.
fail to do sth › to not do what is necessary or expected: John failed to turn up for football practice yesterday.
EXAM [I, T] › to not pass a test or an exam, or to decide that someone has not passed: I'm worried about failing my driving test.
STOP WORKING [I] › to stop working normally, or to become weaker: Two of the plane's engines had failed. My eyesight's beginning to fail.
NOT HELPING [T] › to stop being helpful or useful to someone when they need you: The government is failing the poor and unemployed.
I fail to see/understand › used to show that you do not accept something: [+ question word] I fail to see why you cannot work on a Sunday.