onion

/ˈʌn.jən/

//ˈʌn.jən// noun

"onion" is a 5-letter English headword indexed on PlainSpell.

The verdict

“onion” is a regularly-used English word, ranked #8,464 in English word frequency and used as a noun.

#8,464
frequency rank, English
5
letters
6
tracked misspellings
14
confusable pairs

According to Wiktionary data (CC BY-SA, analyzed May 6, 2026) - A monocotyledonous plant (Allium cepa), allied to garlic, used as vegetable and spice.

Visual similarity to commonly confused words

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

onion vs ono
60% similar
onion vs onto
60% similar
onion vs Oxon
40% similar

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

Key facts for onion
PropertyValue
Headwordonion
LanguageEnglish
Part of speechNoun
IPA/ˈʌn.jən/
Letters5
Frequency rank#8,464
Misspellings tracked6
Confusable pairs14
SourceWiktionary (kaikki.org)

Where “onion” 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). onion 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 onion is 5 letters long, classified as a noun, and transcribed in the International Phonetic Alphabet as /ˈʌn.jən/. Corpus data places it at rank #8,464 in overall English word frequency, indicating it appears regularly in written and spoken text. Wiktionary records 8 distinct senses for this headword, so context determines which meaning a reader should apply.

Our generated misspelling index lists 6 likely wrong-spelling variants for onion, with forms such as "noion", "oinon", and "onino". 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 14 confusable-pair relationships, "ono", "onto", "Oxon", and more, where similar look or sound leads writers to substitute one word for another in context.

Etymologically, the entry records: From Middle English onyoun, oynoun, from Old French oignon, from Latin ūniōnem, accusative of ūniō (“onion”), which had also been borrowed into Old English as yne, ynnelēac (“onion”) (> Middle English hynne-leac, henne-leac). Also displaced Middle English k… The correct English form is onion, spelled O-N-I-O-N.

Definition

  1. 1
    A monocotyledonous plant (Allium cepa), allied to garlic, used as vegetable and spice.
  2. 2
    The bulb of such a plant.
  3. 3
    Any of various plants, mostly of the genus Allium, that are more or less similar to Allium cepa.
  4. 4
    Of a drug, an ounce.
  5. 5
    A ball.
  6. 6
    A watch-seal.
  7. 7
    Alternative letter-case form of Onion (“an inhabitant of Bermuda; a Bermudian”).
  8. 8
    Soy, particularly when used in compound words related to the soy boy stereotype.

Etymology

From Middle English onyoun, oynoun, from Old French oignon, from Latin ūniōnem, accusative of ūniō (“onion”), which had also been borrowed into Old English as yne, ynnelēac (“onion”) (> Middle English hynne-leac, henne-leac). Also displaced Middle English knelek (literally “knee-leek”) and the inherited term ramsons. * (soy): Stems from a 4chan word filter which changes the word soy to onions. The word filter was implemented in relation to the "alpha onion eater" meme, which is depicted as the direct opposite of the soy boy.

Synonyms

This word in other languages

Common misspellings

Also misspelled as: noion,oinon,onino,onionn,onnion,onoin

Misspelling Pattern Breakdown

How far each generated variant is from the correct spelling of onion - counted as single-character edits (an insertion, a deletion, or a substituted letter). The larger the bar, the easier the typo is to spot; one-edit slips are the ones that sneak past readers.

noion2oinon2onino2onionn1onnion1onoin2
Edit distance from "onion"

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 "onion"?
"onion" is spelled O-N-I-O-N. The IPA pronunciation is /ˈʌn.jən/.
What does "onion" mean?
As a noun, "onion" means: A monocotyledonous plant (Allium cepa), allied to garlic, used as vegetable and spice.
What words are commonly confused with "onion"?
"onion" is commonly confused with "ono", "onto", "Oxon". These words look or sound similar but have different meanings. PlainSpell provides detailed comparisons for each pair.
How do you pronounce "onion"?
The IPA (International Phonetic Alphabet) transcription for "onion" is /ˈʌn.jən/. 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 "onion"?
From Middle English onyoun, oynoun, from Old French oignon, from Latin ūniōnem, accusative of ūniō (“onion”), which had also been borrowed into Old English as yne, ynnelēac (“onion”) (> Middle English hynne-leac, henne-leac). Also displaced Middle... 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 “onion”

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

  • The one correct English spelling is O-N-I-O-N - every other letter order is a misspelling in standard orthography.
  • Say it as /ˈʌn.jən/ (IPA); tap the speaker on the pronunciation badge to hear it where audio exists.
  • Don't mix it up with “ono” - see the side-by-side comparison. onion vs ono
  • 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