Omicron

Omicron uc lc.svg
Greek alphabet
Αα Alpha Νν Nu
Ββ Beta Ξξ Xi
Γγ Gamma Οο Omicron
Δδ Delta Ππ Pi
Εε Epsilon Ρρ Rho
Ζζ Zeta Σσς Sigma
Ηη Eta Ττ Tau
Θθ Theta Υυ Upsilon
Ιι Iota Φφ Phi
Κκ Kappa Χχ Chi
Λλ Lambda Ψψ Psi
Μμ Mu Ωω Omega
Other characters
Digamma uc lc.svg Digamma Greek Stigma.svg Stigma
Greek Heta.svg Heta Greek San.svg San
Qoppa Q-and-Z-shaped.svg Qoppa Greek Sampi 2 shapes.svg Sampi
Greek diacritics

Omicron (uppercase Ο, lowercase ο, literally "small o": Όμικρον, o mikron, micron meaning 'small' in contrast to omega) is the 15th letter of the Greek alphabet. In the system of Greek numerals it has a value of 70. It is rarely used in mathematics because it is indistinguishable from the Latin letter O and easily confused with the digit 0. This letter is derived from the Phoenician letter Ayin. In modern Greek, Omicron represents the sound IPA: [ɔ]. Letters that arose from omicron include Roman O and Cyrillic O.

In Unicode the capital letter is codepoint U+039F and the lowercase is U+03BF.

The upper-case letter of omicron (O) was originally used as a symbol for Big O notation, representing the asymptotic rate of growth of a function in mathematics.

In popular culture

References