Definition of "Fail" :
verb: get worse
verb: stop operating or functioning
"The engine failed on the way to town."
verb: prove insufficient
"The water supply for the town failed after a long drought."
verb: disappoint, prove undependable to; abandon, forsake
"His sense of smell failed him this time."
verb: become bankrupt or insolvent; fail financially and close
"A number of banks failed that year."
verb: fall short in what is expected
"She failed in her obligations as a good daughter-in-law."
verb: fail to get a passing grade
"She studied hard but failed nevertheless."
verb: judge unacceptable
"The teacher failed six students."
verb: be unsuccessful
"Where do today's public schools fail?."
verb: fail to do something; leave something undone
"She failed to notice that her child was no longer in his crib."
verb: be unable
"I fail to understand your motives."