fail

FAYL/feɪl/

17 meanings of fail

1
be unsuccessfulverbintransitive
To not succeed in an attempt or undertaking.
Most startups fail within their first few years.
The rescue mission failed despite careful planning.
UsageUse fail in to name the attempt, as in governments failing in their quest.
Similarfounder, fold, flop, collapse, miscarry
Oppositesucceed, thrive, prosper, triumph
2
not carry outverbtransitive
To not do or accomplish something intended, expected, or required, including neglecting a duty or responsibility.
The committee failed to reach an agreement.
Tenants who fail to pay rent on time risk eviction.
UsageFollowed by to + verb: fail to pay, failed to reach an agreement.
Similarneglect, omit
Oppositemanage, succeed
Note
The construction often reports no real attempt at all. A truck that failed to start was not trying, so the phrase can mean little more than "did not." The same pattern covers neglect, where the omission is a fault, as when a report fails to take something into account.
3
go wrong (machine)verbintransitive
Of a machine or system, to stop operating correctly.
The backup generator failed during the storm.
Brakes can fail if they are not maintained.
Similarmalfunction, break, die
Oppositework, function, operate
4
be no helpverbtransitive
To let down or prove insufficient for someone; to disappoint expectations or desert in a time of need.
His memory failed him during the exam.
Leaders too often fail the very people they promised to protect.
UsageUsually something fails someone: his memory failed him, her courage failed her.
Similardesert, disappoint, abandon, betray, forsake
Oppositesupport
Note
The person let down is the object, and the subject is whatever proves wanting: a memory, a leader, a child. The King James Bible of 1611 shows the older shape: "There shall not fail thee (said he) a man on the throne," meaning you will never lack one. Read it that way and modern uses follow naturally. When memory fails someone, it is not there when needed.
Checked 31 Oct 2026 · 3 facts
The King James Bible was first published in 1611. wwwe.lib.cam.ac.uk
In 1 Kings 2:4, the wording includes the parenthesis “(said he)” between “thee” and “a man”. en.wikisource.org
The older construction describes someone or something being wanting or insufficient for another person. en.wiktionary.org
5
go bankruptverbintransitive
To become unable to pay one's debts or meet business obligations; to go bankrupt.
Several lenders failed when borrowers stopped repaying their loans.
A business that cannot pay its debts will eventually fail.
Similarcollapse, fold, founder, crash
Oppositethrive, prosper, flourish
6
adjectiveslangUS
Inadequate or unacceptable; falling short of what is wanted.
My brother tried to fix the sink himself, and the result was totally fail, with water all over the floor.
Wearing a heavy wool suit to a beach wedding in July was so fail, and he knew it right away.
UsageUse after a linking verb, as in that was so fail. In formal writing, use unsuccessful or inadequate.
Similarlame, inadequate, bad, awful, pathetic
Oppositegreat, awesome
7
grow weakverb
To become weaker, less, or insufficient, or to stop being present or adequate, as of health, eyesight, light, or crops.
The daylight failed quickly behind the mountains.
When earnestly they seek / Such proof, conclude they then begin to fail.
1667, John Milton, Paradise Lost
UsageOften begin to fail or start to fail, as in her health began to fail; also failing eyesight.
Note
Milton's Paradise Lost (1667) has "conclude they then begin to fail," and begin is a natural partner. This sense describes a falling away in progress rather than a single breakdown like a machine's failure.
Checked 2 Nov 2026 · 4 facts
John Milton wrote Paradise Lost. en.wikisource.org
Paradise Lost was first published in 1667. en.wikisource.org
Paradise Lost contains the quoted words, spoken by Adam to Eve. en.wikisource.org
The quotation illustrates the historical sense of declining or falling away. en.wiktionary.org

Less common meanings

8
not pass (exam)verbtransitive or intransitive
To receive one or more non-passing grades in school or other academic work.
She failed chemistry but retook it the following semester.
Students who fail more than two courses must meet an advisor.
UsageName the test or course directly: fail chemistry, fail the exam; you can also just fail.
Similarflunk
Oppositepass
9
give an Fverbtransitive
To give a student a non-passing grade in a course or examination.
The examiner failed half the class that year.
Instructors who fail too many students draw scrutiny.
Similarflunk
Oppositepass
10
flopnounslangUScountable or uncountable
Slang: something that is a complete failure or embarrassingly bad, or such poor quality in general.
Critics called the sequel a fail compared to the original.
The whole marketing campaign was an embarrassing fail.
UsageOften an epic fail or a total fail. In formal writing, failure is usual.
Similarfailure, flop, fiasco, disaster, dud
Oppositesuccess, win, triumph, hit
11
no-pass marknouncountable or uncountable
A non-passing grade awarded in an academic examination.
Two fails in one semester put her on academic probation.
A fail in the practical test means repeating the entire course.
UsageOften get a fail, or a fail in a test.
Oppositepass
12
trade not completednouncountable or uncountable
An instance of failure, especially a financial transaction, such as a trade or delivery, that is not completed.
The clearinghouse reported a fail on the bond delivery.
Repeated fails in settlement triggered an audit.
Similarfailure
13
verbobsoletetransitive
To miss attaining something, or to lose it.
though that seat of earthly bliss be failed
1671, John Milton, “The Fourth Book”
Note
Milton could make the prize itself the object. In Paradise Regain'd (1671) he writes "though that seat of earthly bliss be failed," meaning lost or not won.
Checked 2 Nov 2026 · 4 facts
John Milton wrote Paradise Regain'd. en.wikisource.org
Paradise Regain'd was first published in 1671. en.wikisource.org
Paradise Regain'd contains the quoted words, sung by the angelic choir. gutenberg.org
The quotation exemplifies transitive fail meaning to lose or miss attaining something. en.wiktionary.org
14
verbarchaic
To be short of something; to lack or be deficient in it, used with "of."
If ever they fail of beauty, this failure is not to be attributed to their size.
1757, Edmund Burke, A Philosophical Enquiry into the Origin of Our Ideas of the Sublime and Beautiful
Note
Here the one who lacks is the subject, and the thing lacked follows of. Edmund Burke's Philosophical Enquiry (1757) says of small things that "if ever they fail of beauty," the cause is not their size.
Checked 2 Nov 2026 · 4 facts
In the cited construction, the subject lacks the quality named after of. gutenberg.org
Edmund Burke wrote the Philosophical Enquiry. en.wikipedia.org
The work was first published in 1757, as its first-edition title page confirms. en.wikisource.org
Burke uses the quoted words about small things and says their failure of beauty cannot be attributed to size. gutenberg.org
15
verbobsolete
To make an error in judgment; to be mistaken.
Which ofttimes may succeed, so as perhaps / Shall grieve him, if I fail not.
1667, John Milton, Paradise Lost
Note
Here the failure is one of judgment. In Paradise Lost (1667), Milton's "Shall grieve him, if I fail not" means "if I am not mistaken." Read today, if I fail not sounds like a vow to succeed, so the line is easily misheard.
Checked 2 Nov 2026 · 4 facts
John Milton wrote Paradise Lost. en.wikipedia.org
Paradise Lost was first published in 1667. wwwe.lib.cam.ac.uk
The quotation is exact and occurs in Book I, spoken by Satan, identified as the Arch-fiend. en.wikisource.org
Fail here means to err in judgment, so 'if I fail not' means 'if I am not mistaken.' en.wiktionary.org
16
verbobsolete
Of a person, to perish or lose one's life.
had the king in his last sickness failed
1613, William Shakespeare, [John Fletcher]
Note
In Shakespeare and Fletcher's Henry VIII (written 1613), "had the king in his last sickness failed" means had he died of it. It is the end point of the "grow weaker" meaning, and that closeness is the trap: a modern reader hears only weakening.
Checked 2 Nov 2026 · 5 facts
William Shakespeare and John Fletcher wrote Henry VIII. en.wikipedia.org
1613 is the accepted composition date of Henry VIII. en.wikipedia.org
The quotation occurs in Act I, scene ii, spoken by the Surveyor while reporting Buckingham's words. folger.edu
Failed here means died, making the clause a hypothetical reference to the king dying during his illness. en.wiktionary.org
Fail also has the related sense of becoming weaker. en.wiktionary.org
17
noun
A slice of turf cut from open grassland.

Practice

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Origin

This word comes from Middle English failen, borrowed from Old French falir, which goes back to Vulgar Latin *fallire, an altered form of Latin fallere ('to deceive, disappoint'). It is thought to derive from a Proto-Indo-European root meaning 'to lie, deceive' or possibly one meaning 'to stumble.'

Checked 31 Oct 2026 · 4 facts

English fail comes from Middle English failen, borrowed from Old French falir. en.wiktionary.org
Old French falir derives from Vulgar Latin *fallire, an alteration of Latin fallere, meaning 'to deceive, disappoint'. en.wiktionary.org
A Proto-Indo-European root meaning 'to lie, deceive' has been proposed. en.wiktionary.org
An alternative proposed Proto-Indo-European root means 'to stumble'. en.wiktionary.org