Omicron

From Wikipedia, the free encyclopedia

Greek alphabet
Α α Alpha	Ν ν Nu
Β β Beta	Ξ ξ Xi
Γ γ Gamma	Ο ο Omicron
Δ δ Delta	Π π Pi
Ε ε Epsilon	Ρ ρ Rho
Ζ ζ Zeta	Σ σ ς Sigma
Η η Eta	Τ τ Tau
Θ θ Theta	Υ υ Upsilon
Ι ι Iota	Φ φ Phi
Κ κ Kappa	Χ χ Chi
Λ λ Lambda	Ψ ψ Psi
Μ μ Mu	Ω ω Omega
Obsolete letters
Ϝ ϝ Digamma	Ϻ ϻ San
Ϙ ϙ Qoppa	Ϡ ϡ Sampi
Ϛ ϛ Stigma	Ϸ ϸ Sho

Omicron (upper case Ο, lower case ο, literally "small o": o mikron, micron meaning 'small') is the 15th letter of the Greek alphabet. In the system of Greek numerals it has a value of 70. It is not used in mathematics because it is indistinguishable from the Latin letter O. Indeed, it is not widely used because of confusion with the digit 0.

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:

• The Big O notation, representing the asymptotic rate of growth of a function in mathematics.