Merriam-Webster Logo
  • Dictionary
  • Thesaurus
  • Medical
  • Scrabble
  • Spanish Central
  • Learner's Dictionary


verb \ˈprüv\

Simple Definition of prove

  • : to show the existence, truth, or correctness of (something) by using evidence, logic, etc.

  • : to show that (someone or something) has a particular quality, ability, etc.

  • : to turn out to be

Full Definition of prove

provedproved or prov·en play \ˈprü-vən, British also ˈprō-\ prov·ing play \ˈprü-viŋ\

  1. transitive verb
  2. 1 archaic :  to learn or find out by experience

  3. 2 a :  to test the truth, validity, or genuineness of <the exception proves the rule> <prove a will at probate> b :  to test the worth or quality of; specifically :  to compare against a standard —sometimes used with up or out c :  to check the correctness of (as an arithmetic result)

  4. 3 a :  to establish the existence, truth, or validity of (as by evidence or logic) <prove a theorem> <the charges were never proved in court> b :  to demonstrate as having a particular quality or worth <the vaccine has been proven effective after years of tests> <proved herself a great actress>

  5. 4 :  to show (oneself) to be worthy or capable <eager to prove myself in the new job>

  6. intransitive verb
  7. :  to turn out especially after trial or test <the new drug proved effective>

prov·able play \ˈprü-və-bəl\ adjective
prov·able·ness noun
prov·ably play \-blē\ adverb
prov·er play \ˈprü-vər\ noun

Usage Discussion of prove

The past participle proven, originally the past participle of preve, a Middle English variant of prove that survived in Scotland, has gradually worked its way into standard English over the past three and a half centuries. It seems to have first become established in legal use and to have come only slowly into literary use. Tennyson was one of its earliest frequent users, probably for metrical reasons. It was disapproved by 19th century grammarians, one of whom included it in a list of “words that are not words.” Surveys made some 50 or 60 years ago indicated that proved was about four times as frequent as proven. But our evidence from the last 30 or 35 years shows this no longer to be the case. As a past participle proven is now about as frequent as proved in all contexts. As an attributive adjective <proved or proven gas reserves> proven is much more common than proved.

Examples of prove

  1. The charges against him were never proved in court.

  2. The government failed to prove its case.

  3. It could not be proven that the suspect stole the money.

  4. A person who is charged with a crime is considered innocent until proved guilty.

  5. mathematicians trying to prove a theorem

  6. To prove her point, she got out the old research.

  7. The tests proved the vaccine to be effective.

  8. Her second album was a hit that proved her critics wrong.

Origin of prove

Middle English, from Anglo-French prover, pruver, from Latin probare to test, prove, from probus good, honest, from pro- for, in favor + -bus (akin to Old English bēon to be) — more at pro-, be

First Known Use: 13th century

PROVE Defined for Kids


verb \ˈprüv\

Definition of prove

provedproved or prov·en \ˈprü-vən\prov·ing

  1. 1 :  to show the truth or existence of something with facts <I can prove he's guilty.>

  2. 2 :  to turn out to be <The climb proved more difficult than they had expected.>

  3. 3 :  to check the correctness of <prove the math theory>

  4. 4 :  to test by experiment or by a standard <Tests proved that the vaccine is effective.>

Seen and Heard

What made you want to look up prove? Please tell us where you read or heard it (including the quote, if possible).


February 8, 2016

to clear from accusation or blame

Get Word of the Day daily email!


Take a 3-minute break and test your skills!


Which of the following refers to thin, bending ice, or to the act of running over such ice?

kittly-benders spindrift pince-nez duvet
Name That Thing

10 quick questions: hear them, spell them, and see how your skills compare to the crowd.


Test Your Knowledge - and learn some interesting things along the way.