once

/wʌn(t)s/

//wʌn(t)s// adv

By · According to Wiktionary data (CC BY-SA) ·

"once" is a 4-letter English headword indexed on PlainSpell.

The verdict

“once” is in the everyday core of English, ranked #275 in English word frequency and used as an adverb.

#275
frequency rank, English
4
letters
5
tracked misspellings
20
confusable pairs

According to Wiktionary data (CC BY-SA, analyzed May 6, 2026) - One and only one time.

Visual similarity to commonly confused words

How many letter changes separate each confused pair (Levenshtein distance, normalized).

once vs one
75% similar
once vs owe
50% similar
once vs ore
50% similar

Source: PlainSpell confusable corpus (Wiktionary, CC BY-SA).

Key facts for once
PropertyValue
Headwordonce
LanguageEnglish
Part of speechAdverb
IPA/wʌn(t)s/
Letters4
Frequency rank#275
Misspellings tracked5
Confusable pairs20
SourceWiktionary (kaikki.org)

Where “once” sits in English frequency

Every-word frequency runs from the handful of words we use constantly (left) to the long tail used once in a blue moon (right). once lands here:

#1#100#1K#10K#100K
← used constantlyrarely used →

Scale is logarithmic (each tick is 10× rarer). Source: FrequencyWords open word-frequency list.

Spelling & Dictionary Insight

The English entry for once is 4 letters long, classified as an adverb, and transcribed in the International Phonetic Alphabet as /wʌn(t)s/. Corpus data places it at rank #275 in overall English word frequency, putting it firmly in the everyday core of the language. Wiktionary records 5 distinct senses for this headword, so context determines which meaning a reader should apply.

Our generated misspelling index lists 5 likely wrong-spelling variants for once, with forms such as "noce", "ocne", and "oncce". Each of these forms differs from the correct spelling by one small edit: a doubled letter, a dropped silent letter, or a substituted vowel. It also participates in 20 confusable-pair relationships, "one", "owe", "ore", and more, a pairing that trips writers up because the two words share enough sound or shape to blur together.

Etymologically, the entry records: From Middle English ones, from Old English ānes, a remodelling (after ān (“one”)) of ǣnes, itself an extension of ǣne (“once”) with the genitive suffix -es. Equivalent to one + -s. Cognate with Saterland Frisian enst, insen (“once”), West Frisian iens (“onc… The correct English form is once, spelled O-N-C-E.

Definition

  1. 1
    One and only one time.
  2. 2
    Formerly; during some period in the past.
  3. 3
    At any time; ever.
  4. 4
    One day, someday.
  5. 5
    Multiplied by one: indicating that a number is multiplied by one.

Etymology

From Middle English ones, from Old English ānes, a remodelling (after ān (“one”)) of ǣnes, itself an extension of ǣne (“once”) with the genitive suffix -es. Equivalent to one + -s. Cognate with Saterland Frisian enst, insen (“once”), West Frisian iens (“once”), Dutch eens (“once”), German Low German eens, ins (“once”), German einst (“once”). More at one (including regarding the development of the pronunciation) and -s.

Synonyms

formerlyonceoncetyancewunst

Antonyms

four timesoftenthricetwice

This word in other languages

antiguamente(Español)une fois(Français)einmal(Deutsch)outrora(Português)

Common misspellings

Also misspelled as: noce,ocne,oncce,onec,onnce

Misspelling Pattern Breakdown

How far each generated variant is from the correct spelling of once - expressed in single-character edits (insert, delete, or swap one letter). Bigger bars stand out at a glance; a one-edit slip is the hardest to catch.

noce2ocne2oncce1onec2onnce1
Edit distance from "once"

Definitions, pronunciation, and etymology for this entry are drawn from Wiktionary via the kaikki.org structured extract (CC BY-SA); frequency ordering uses the FrequencyWords open word-frequency list (2018 English corpus, MIT). See the methodology for how each field is sourced and updated.

Frequently Asked Questions

How do you spell "once"?
"once" is spelled O-N-C-E. The IPA pronunciation is /wʌn(t)s/.
What does "once" mean?
As an adverb, "once" means: One and only one time.
What words are commonly confused with "once"?
"once" is commonly confused with "one", "owe", "ore". These words look or sound similar but have different meanings. PlainSpell provides detailed comparisons for each pair.
How do you pronounce "once"?
The IPA (International Phonetic Alphabet) transcription for "once" is /wʌn(t)s/. 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 "once"?
From Middle English ones, from Old English ānes, a remodelling (after ān (“one”)) of ǣnes, itself an extension of ǣne (“once”) with the genitive suffix -es. Equivalent to one + -s. Cognate with Saterland Frisian enst, insen (“once”), West Frisian ... 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.

Using “once”

The practical upshot for anyone who landed here from a spell-check.

  • The one correct English spelling is O-N-C-E - every other letter order is a misspelling in standard orthography.
  • Say it as /wʌn(t)s/ (IPA); tap the speaker on the pronunciation badge to hear it where audio exists.
  • Don't mix it up with “one” - see the side-by-side comparison. once vs one
  • Browse more English words and confusable pairs in the same reference. English words
Data Source

Wiktionary (via kaikki.org), licensed under CC BY-SA & GFDL. Word ordering uses an open word-frequency list; misspelling variants are generated by edit-distance from the correct headword.

Source: Wiktionary (via kaikki.org) Structured Wiktionary extract

Source: FrequencyWords open word-frequency list FrequencyWords open word-frequency list