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proof

Definition, pronunciation, etymology, and usage for the English word. Free spelling reference powered by Wiktionary.

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5 characters

Language

English

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Detailed reference entry for the English word "proof", 5-letters, with pronunciation in International Phonetic Alphabet notation, etymology traced through Germanic and Romance roots where applicable, common misspelling variants catalogued from Hunspell error dictionaries, and usage frequency ranked against the top 100,000 English words in the Wordfreq corpus. PlainSpell covers English, Spanish, Portuguese, French, and German spelling with confusable-pair detection that highlights visually and phonetically similar words. This entry for "proof" includes synonyms, antonyms, homophones, and cross-language translation pointers sourced from Wiktionary via the kaikki.org extract. Whether you are verifying the correct spelling of "proof" for academic writing, checking homophone confusion, or exploring etymological origins, this page provides a citation-backed, free reference that requires no sign-up.

proof is aEnglishnoun. It means: An effort, process, or operation designed to establish or discover a fact or truth; an act of testing; a test; a trial. Pronounced /pɹuːf/. It ranks #2,052 in English word frequency. Often confused with pros and prop.

Key facts for proof
PropertyValue
Headwordproof
LanguageEnglish
Part of speechNoun
IPA/pɹuːf/
Letters5
Frequency rank#2,052
Misspellings tracked7
Confusable pairs20
SourceWiktionary (kaikki.org)

Frequency rank visualization

Position of proof in English word frequency (lower rank = more common)

Source: Wordfreq corpus

Spelling & Dictionary Insight

The English entry for proof is 5 letters long, classified as anoun, and transcribed in the International Phonetic Alphabet as /pɹuːf/. Corpus data places it at rank #2,052 in overall English word frequency, indicating it appears regularly in written and spoken text.Wiktionary records 11 distinct senses for this headword, so context determines which meaning a reader should apply.

Our Hunspell-derived misspelling index lists 7 documented wrong-spelling variants for proof, with forms such as "porof", "pproof", and "prof". Each variant represents a distinct typo pattern that appears often enough in corpora to be worth flagging, typically a doubled-consonant error, a silent-letter drop, or a vowel substitution.It also participates in 20 confusable-pair relationships, "pros", "prop", "Prot", and more, where similar look or sound leads writers to substitute one word for another in context.

Etymologically, the entry records: From Middle English proof, from Old French prove, from Late Latin proba (“a proof”), from Latin probō (“to prove”); see prove; compare also the doublet probe. Root origin matters for spelling because borrowed morphemes (Greek, Latin, Old French, Old English) carry their source-language orthographic conventions into modern English, which is why historical etymology is often the cleanest predictor of whether a cluster like "-ough", "-eau", or "-tion" will appear. For readers arriving here from a spelling check, the authoritative guidance is: the correct English form is proof, spelled P-R-O-O-F, and any other sequence of those letters, regardless of how natural it feels, is a misspelling in standard orthography.

Definition

  1. 1
    An effort, process, or operation designed to establish or discover a fact or truth; an act of testing; a test; a trial.
  2. 2
    The degree of evidence which convinces the mind of any truth or fact, and produces belief; a test by facts or arguments which induce, or tend to induce, certainty of the judgment; conclusive evidence; demonstration.
  3. 3
    The quality or state of having been proved or tried; firmness or hardness which resists impression, or does not yield to force; impenetrability of physical bodies.
  4. 4
    Experience of something.
  5. 5
    Firmness of mind; stability not to be shaken.
  6. 6
    A proof sheet; a trial impression, as from type, taken for correction or examination.
  7. 7
    A limited-run high-quality strike of a particular coin, originally as a test run, although nowadays mostly for collectors' sets.
  8. 8
    A sequence of statements consisting of axioms, assumptions, statements already demonstrated in another proof, and statements that logically follow from previous statements in the sequence, and which concludes with a statement that is the object of the proof.
  9. 9
    A process for testing the accuracy of an operation performed. Compare prove, transitive verb, 5.
  10. 10
    Armour of excellent or tried quality, and deemed impenetrable; properly, armour of proof.
  11. 11
    A measure of the alcohol content of liquor. Originally, in Britain, 100 proof was defined as 57.1% by volume (no longer used). In the US, 100 proof means that the alcohol content is 50% of the total volume of the liquid; thus, perfectly pure absolute alcohol would be 200 proof.

Etymology

From Middle English proof, from Old French prove, from Late Latin proba (“a proof”), from Latin probō (“to prove”); see prove; compare also the doublet probe.

This word in other languages

Common misspellings

Also misspelled as: porof,pproof,prof,profo,prooff,prroof,rpoof

Misspelling Pattern Breakdown

Relative frequency of common misspelling types for proof

Misspelling Variants of "proof"

porof5pproof6prof4profo5prooff6prroof6rpoof5
Misspelling Variants of "proof"

Frequency rank: #2,052 in English

Frequently Asked Questions

How do you spell "proof"?
"proof" is spelled P-R-O-O-F. The IPA pronunciation is /pɹuːf/.
What does "proof" mean?
As a noun, "proof" means: An effort, process, or operation designed to establish or discover a fact or truth; an act of testing; a test; a trial.
What words are commonly confused with "proof"?
"proof" is commonly confused with "pros", "prop", "Prot". These words look or sound similar but have different meanings. PlainSpell provides detailed comparisons for each pair.
How do you pronounce "proof"?
The IPA (International Phonetic Alphabet) transcription for "proof" is /pɹuːf/. Click the speaker icon on the pronunciation badge above to hear it spoken aloud where audio is available.
What is the origin of the word "proof"?
From Middle English proof, from Old French prove, from Late Latin proba (“a proof”), from Latin probō (“to prove”); see prove; compare also the doublet probe. See the full etymology section above for more details.
Is PlainSpell free to use?
Yes, PlainSpell is a completely free word reference. You can look up definitions, pronunciations, confusable pairs, homophones, and spelling corrections across 5 languages without any sign-up or subscription.

Nearby English words

Other entries that begin with the letter P in our English index:

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Data Source: Wiktionary (via kaikki.org), licensed under CC BY-SA & GFDL. Frequency data from Wordfreq. Misspellings derived from Hunspell dictionaries.