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omicron

noun om·i·cron \ ˈä-mə-ˌkrän , ˈō- , British ō-ˈmī-(ˌ)krän \
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Definition of omicron

: the 15th letter of the Greek alphabet — see Alphabet Table

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Origin and Etymology of omicron

Middle English, from Greek o mikron, literally, small o

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