io
/ˈaɪəʊ/
"io" is a 2-letter English headword indexed on PlainSpell.
The verdict
“io” is a moderately-common English word, ranked #16,946 in English word frequency and used as a noun.
- #16,946
- frequency rank, English
- 2
- letters
- 20
- confusable pairs
According to Wiktionary data (CC BY-SA, analyzed May 6, 2026) - A type of moth, the io moth.
Visual similarity to commonly confused words
How many letter changes separate each confused pair (Levenshtein distance, normalized).
Source: PlainSpell confusable corpus (Wiktionary, CC BY-SA).
| Property | Value |
|---|---|
| Headword | io |
| Language | English |
| Part of speech | Noun |
| IPA | /ˈaɪəʊ/ |
| Letters | 2 |
| Frequency rank | #16,946 |
| Misspellings tracked | 0 |
| Confusable pairs | 20 |
| Source | Wiktionary (kaikki.org) |
Where “io” sits in English frequency
Spelling & Dictionary Insight
The English entry for io is 2 letters long, classified as a noun, and transcribed in the International Phonetic Alphabet as /ˈaɪəʊ/. Corpus data places it at rank #16,946 in overall English word frequency, marking it as uncommon enough that many writers pause before typing it. The dominant gloss from Wiktionary reads: "A type of moth, the io moth.".
io has no tracked misspelling variants, and the word's spelling is regular enough that our generator found nothing worth flagging. It also participates in 20 confusable-pair relationships, "is", "it", "IV", 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 New Latin, from Ancient Greek Ἰώ (Iṓ, “Io”). The correct English form is io, spelled I-O.
Definition
- 1A type of moth, the io moth.
Etymology
From New Latin, from Ancient Greek Ἰώ (Iṓ, “Io”).
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
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Using “io”
The practical upshot for anyone who landed here from a spell-check.
- The one correct English spelling is I-O - every other letter order is a misspelling in standard orthography.
- Say it as /ˈaɪəʊ/ (IPA); tap the speaker on the pronunciation badge to hear it where audio exists.
- Don't mix it up with “is” - see the side-by-side comparison. io vs is
- 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.