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omicron

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

Letters

7 characters

Language

English

word origin

Source

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Detailed reference entry for the English word "omicron", 7-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 "omicron" 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 "omicron" for academic writing, checking homophone confusion, or exploring etymological origins, this page provides a citation-backed, free reference that requires no sign-up.

omicron is aEnglishnoun. It means: The 15th letter of the Classical and Modern Greek alphabets (16th in Ancient and Old Greek), used in ordering lists as in naming (astronomy) the 15th star of a constellation or (epidemiology) the 1... Pronounced /ˈɒmɪkɹɒn/.

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Key facts for omicron
PropertyValue
Headwordomicron
LanguageEnglish
Part of speechNoun
IPA/ˈɒmɪkɹɒn/
Letters7
Frequency rank#63,118
Misspellings tracked0
Confusable pairs0
SourceWiktionary (kaikki.org)

Frequency rank visualization

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

Source: Wordfreq corpus

Spelling & Dictionary Insight

The English entry for omicron is 7 letters long, classified as anoun, and transcribed in the International Phonetic Alphabet as /ˈɒmɪkɹɒn/. Corpus data places it at rank #63,118 in overall English word frequency, marking it as uncommon enough that many writers pause before typing it.The dominant gloss from Wiktionary reads: "The 15th letter of the Classical and Modern Greek alphabets (16th in Ancient and Old Greek), used in ordering lists as in naming (astronomy) the 15th star of a constellation or (epidemiology) the 1...".

No frequent misspelling variants are recorded for omicron in our index, suggesting the orthography either follows predictable English patterns or the word is uncommon enough that typo corpora lack signal.It is not paired with a close-neighbour confusable in our dataset, which tends to mean the word is visually distinctive enough to stand on its own.

Etymologically, the entry records: From Latin omicron, from Koine Greek ὂ μῑκρόν (ò mīkrón, “little o”), named in contrast with omega (“big o”). The uncommon form omicra is similarly borrowed from Latin and Greek. The use for designating stars in a constellation—typically in order of apparen… 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 omicron, spelled O-M-I-C-R-O-N, and any other sequence of those letters, regardless of how natural it feels, is a misspelling in standard orthography.

Definition

  1. 1
    The 15th letter of the Classical and Modern Greek alphabets (16th in Ancient and Old Greek), used in ordering lists as in naming (astronomy) the 15th star of a constellation or (epidemiology) the 15th discovered major variant of a disease.

Etymology

From Latin omicron, from Koine Greek ὂ μῑκρόν (ò mīkrón, “little o”), named in contrast with omega (“big o”). The uncommon form omicra is similarly borrowed from Latin and Greek. The use for designating stars in a constellation—typically in order of apparent brightness—began with Johann Bayer's 1603 Uranometria.

Frequency rank: #63,118 in English

Frequently Asked Questions

How do you spell "omicron"?
"omicron" is spelled O-M-I-C-R-O-N. The IPA pronunciation is /ˈɒmɪkɹɒn/.
What does "omicron" mean?
As a noun, "omicron" means: The 15th letter of the Classical and Modern Greek alphabets (16th in Ancient and Old Greek), used in ordering lists as in naming (astronomy) the 15th star of a constellation or (epidemiology) the 1...
How do you pronounce "omicron"?
The IPA (International Phonetic Alphabet) transcription for "omicron" is /ˈɒmɪkɹɒn/. 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 "omicron"?
From Latin omicron, from Koine Greek ὂ μῑκρόν (ò mīkrón, “little o”), named in contrast with omega (“big o”). The uncommon form omicra is similarly borrowed from Latin and Greek. The use for designating stars in a constellation—typically in order ... See the full etymology section above for more details.
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Nearby English words

Other entries that begin with the letter O 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.