macOS
/ˌmækoʊˈɛs/
"macos" is a 5-letter English headword indexed on PlainSpell.
The verdict
“macOS” is a moderately-common English word, ranked #28,283 in English word frequency and used as a proper noun.
- #28,283
- frequency rank, English
- 5
- letters
- 7
- tracked misspellings
- 20
- confusable pairs
According to Wiktionary data (CC BY-SA, analyzed May 6, 2026) - A major operating system, formerly known as OS X (and before that as Mac OS X), used on laptop and desktop computers by Apple Inc.
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 | macOS |
| Language | English |
| Part of speech | Proper noun |
| IPA | /ˌmækoʊˈɛs/ |
| Letters | 5 |
| Frequency rank | #28,283 |
| Misspellings tracked | 7 |
| Confusable pairs | 20 |
| Source | Wiktionary (kaikki.org) |
Where “macOS” sits in English frequency
Spelling & Dictionary Insight
The English entry for macOS is 5 letters long, classified as a proper noun, and transcribed in the International Phonetic Alphabet as /ˌmækoʊˈɛs/. Corpus data places it at rank #28,283 in overall English word frequency, marking it as uncommon enough that many writers pause before typing it. The dominant gloss from Wiktionary reads: "A major operating system, formerly known as OS X (and before that as Mac OS X), used on laptop and desktop computers by Apple Inc.".
Our generated misspelling index lists 7 likely wrong-spelling variants for macOS, with forms such as "amcos", "maccos", and "macoss". Every one of these variants traces to a single-character edit -- an added or dropped letter, a swapped consonant, or a vowel swap -- the kind of slip a spell-checker is built to catch. It also participates in 20 confusable-pair relationships, "mao", "MoS", "MCS", and more, since the words sound or look close enough that writers reach for the wrong one mid-sentence.
Etymologically, the entry records: From Mac (“Macintosh”) + OS (“operating system”). The correct English form is macOS, spelled M-A-C-O-S.
Definition
- 1A major operating system, formerly known as OS X (and before that as Mac OS X), used on laptop and desktop computers by Apple Inc.
Etymology
From Mac (“Macintosh”) + OS (“operating system”).
This word in other languages
Common misspellings
Also misspelled as: amcos,maccos,macoss,macso,maocs,mcaos,mmacos
Misspelling Pattern Breakdown
How far each generated variant is from the correct spelling of macOS - 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.
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 “macOS”
The practical upshot for anyone who landed here from a spell-check.
- The one correct English spelling is M-A-C-O-S - every other letter order is a misspelling in standard orthography.
- Say it as /ˌmækoʊˈɛs/ (IPA); tap the speaker on the pronunciation badge to hear it where audio exists.
- Don't mix it up with “mao” - see the side-by-side comparison. macOS vs mao
- 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.