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Idioms

    by chance, without plan or intent; accidentally: I met her again by chance in a department store in Paris.
    on the chance, in the mild hope or against the possibility: I'll wait on the chance that she'll come.
    on the off chance, in the very slight hope or against the very slight possibility.

Origin of chance

1250–1300; Middle English < Old French chance, cheance < Vulgar Latin *cadentia a befalling, happening; see cadenza
Related formschance·less, adjectiveun·chanced, adjective

Synonyms for chance

2. accident, fortuity. 3. contingency. 4. opening. 11. befall. See happen. 13. casual, fortuitous.

Antonyms for chance

1. necessity.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
British Dictionary definitions for on the off chance

chance

noun

  1. the unknown and unpredictable element that causes an event to result in a certain way rather than another, spoken of as a real force
  2. (as modifier)a chance meeting Related adjective: fortuitous
fortune; luck; fate
an opportunity or occasion
a risk; gambleyou take a chance with his driving
the extent to which an event is likely to occur; probability
an unpredicted event, esp a fortunate onethat was quite a chance, finding him here
archaic an unlucky event; mishap
by chance
  1. accidentallyhe slipped by chance
  2. perhapsdo you by chance have a room?
chances are… or the chances are… it is likely (that) …
on the chance acting on the possibility; in case
the main chance the opportunity for personal gain (esp in the phrase an eye to the main chance)

verb

(tr) to risk; hazardI'll chance the worst happening
to happen by chance; be the case by chanceI chanced to catch sight of her as she passed
chance on or chance upon to come upon by accidenthe chanced on the solution to his problem
chance one's arm to attempt to do something although the chance of success may be slight
Derived Formschanceful, adjectivechanceless, adjective

Word Origin for chance

C13: from Old French cheance, from cheoir to fall, occur, from Latin cadere
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Word Origin and History for on the off chance

chance

v.

late 14c., "to come about, to happen," from chance (n.). Meaning "to risk" attested from 1859. Related: Chanced; chancing.

chance

n.

c.1300, "something that takes place, what happens, an occurrence" (good or bad, but more often bad), from Old French cheance "accident, chance, fortune, luck, situation, the falling of dice" (12c., Modern French chance), from Vulgar Latin *cadentia "that which falls out," a term used in dice, from neuter plural of Latin cadens, present participle of cadere "to fall" (see case (n.1)).

In English frequently in plural, chances. The word's notions of "opportunity" and "randomness" are as old as the record of it in English and now all but crowd out the word's original notion of "mere occurrence." Main chance "thing of most importance" is from 1570s, bearing the older sense. The mathematical (and hence odds-making) sense is attested from 1778. To stand a chance (or not) is from 1796.

To take (one's) chances "accept what happens" (early 14c.) is from the old, neutral sense; to take a chance/take chances is originally (by 1814) "participate in a raffle or lottery or game;" extended sense of "take a risk" is by 1826.

Online Etymology Dictionary, © 2010 Douglas Harper
Idioms and Phrases with on the off chance

on the off chance

see under on the chance that.

chance

In addition to the idioms beginning with chance

  • chance it
  • chance on

also see:

  • by chance
  • Chinaman's chance
  • eye to the main chance
  • fat chance
  • fighting chance
  • jump at (the chance)
  • not have an earthly chance
  • on the (off) chance
  • snowball's chance in hell
  • sporting chance
  • stand a chance
  • take a chance
  • take one's chances
The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.