Word Study
omicron
CIDE DICTIONARY
omicron, n. [NL., fr. Gr. Micro-.].
Lit., the little, or short, O, o; the fifteenth letter of the Greek alphabet. [Webster 1913 Suppl.]
OXFORD DICTIONARY
omicron, n. the fifteenth letter of the Greek alphabet (O).
Etymology
Gk, o mikron = small o
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