failed; failing; fails
Definition of fail
(Entry 1 of 2)
1a
: to lose strength : weaken
her health was failing
b
: to fade or die away
until our family line fails
c
: to stop functioning normally
the patient's heart failed
2a
: to fall short
failed in his duty
b
: to be or become absent or inadequate
the water supply failed
c
: to be unsuccessful
the marriage failed
specifically
: to be unsuccessful in achieving a passing grade
took the exam and failed
d
: to become bankrupt or insolvent
banks were failing
1a
: to disappoint the expectations or trust of
her friends failed her
b
: to miss performing an expected service or function for
his wit failed him
2
: to be deficient in : lack
never failed an invincible courage— Douglas MacArthur
3
: to leave undone : neglect
fail to lock the door
4a
: to be unsuccessful in passing
failed chemistry
b
: to grade (someone, such as a student) as not passing
The teacher failed only his two worst students.
fail
nounDefinition of fail (Entry 2 of 2)
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Merriam-Webster unabridged
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Time Traveler for fail
The first known use of fail was in the 13th century
See more words from the same century