omicron
/ˈɒmɪkɹɒn/noun
omicron is spelled O-M-I-C-R-O-N. The wrong spelling people search most is omnicron: about 220 Bing searches a month in the United States (September 2025 to August 2026), about 1 in 10 of all searches for the word. Omicron is a noun meaning “The 15th letter of the Classical and Modern Greek alphabets (16th in Ancient and Old Greek), used in ordering…”. The plural of omicron is omicrons or omicra.
How many letters and syllables are in omicron?
| Letters | 7: O-M-I-C-R-O-N |
|---|---|
| In writing | about once in every 4 million words; the 62,894th most frequent word form |
| Wrong spellings searched | 2; the most searched, omnicron, about 220 Bing searches a month (all of them) |
| Same letters |
Sources: letters and syllables from the English Wiktionary's hyphenation or pronunciation; written frequency: wordfreq 3.1 (a 2021 snapshot of Wikipedia, subtitles, news, books, web text and social media); Bing searches in the United States: the average month from September 2025 to August 2026 (Microsoft Advertising keyword data through DataForSEO, read September 30, 2026); rhymes and same-letter words are computed by PlainSpell from its own word list.
How do you spell omicron?
Omicron is spelled O-M-I-C-R-O-N. 2 wrong spellings are searched or written often enough to measure; together they are about 2 in 10 of the searches for omicron in either form.
Bing searches in the United States: the average month from September 2025 to August 2026 (Microsoft Advertising keyword data through DataForSEO, read September 30, 2026). Wrong spellings are taken from Wiktionary entries tagged "misspelling" and its obsolete or nonstandard forms, Wikipedia's Lists of common misspellings and the codespell dictionary, then measured. The proofreader's marks show the change that corrects each one.
How common is omicron?
Omicron appears about once in every 4 million words in written English, the 62,894th most frequent word form in the list.
Source: written frequency: wordfreq 3.1 (a 2021 snapshot of Wikipedia, subtitles, news, books, web text and social media).
How do you pronounce omicron?
- UK /ˈɒmɪkɹɒn/
- UK /ˈɒmɪkɹən/
- UK /ˈəʊmɪkɹɒn/
Source: English Wiktionary, dump of September 2, 2026 (CC BY-SA 4.0), through kaikki.org (Wiktextract). Recordings: En-us-omicron-2.ogg, LL-Q1860_(eng)-Flame,_not_lame-Omicron.wav, Wikimedia Commons (author and licence on each file's page).
What rhymes with omicron?
No other word on PlainSpell ends in the same sounds as omicron (/ɒmɪkɹɒn/).
Spelled with the same letters in another order: moronic.
Computed by PlainSpell from the pronunciations in the English Wiktionary (dump of September 2, 2026): a rhyme shares every sound from the last stressed vowel to the end; ordered by written frequency (wordfreq 3.1).
Forms of omicron
- omicrons plural
- omicra plural
- omikron
- o
- ο
Source: English Wiktionary, dump of September 2, 2026 (CC BY-SA 4.0), through kaikki.org (Wiktextract).
What does omicron mean?
The meanings the English Wiktionary records, quoted as written there (source below).
noun
- 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.
... They include Mira itself (omicron Ceti) which can be seen shortly before dawn.
- 2
Ellipsis of Omicron variant.
noun
- 1
Ellipsis of Omicron variant.
- 2
Alternative form of omicron (Greek letter) (especially in the majuscule form)
Source: English Wiktionary, dump of September 2, 2026 (CC BY-SA 4.0), through kaikki.org (Wiktextract).
Omicron in Spanish, French, German and Portuguese
In the sense Greek letter:
Source: English Wiktionary, dump of September 2, 2026 (CC BY-SA 4.0), through kaikki.org (Wiktextract). Translations are Wiktionary's, by sense; a linked word has its own PlainSpell page.
Where does omicron come from?
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.
Source: English Wiktionary, dump of September 2, 2026 (CC BY-SA 4.0), through kaikki.org (Wiktextract).