sigma
/ˈsɪɡmə/ noun, adjective, proper noun
Forms sigmas sigmata
- noun The eighteenth letter of the Classical and Modern Greek alphabets (Σ, σ), the twentieth letter of Old and Ancient.
- noun (mathematics) The symbol Σ, used to indicate summation of a set or series.
- noun (statistics) The symbol σ, used to indicate one standard deviation from the mean, particularly in a normal distribution.
- noun (Internet slang) A sigma male (a self-reliant and assertive male).
- adjective (Internet slang) Possessing characteristics of a sigma male.
- proper noun A municipality of Capiz, Philippines.
Etymology
From Ancient Greek σῖγμα (sîgma), probably from the root σῑγ- (sīg-) as seen in σίζω (sízō, “to hiss”) + -μα (-ma, nominal suffix).
Webster’s 1913
- noun The Greek letter S, or s). It originally had the form of the English C.
Sources: Wiktionary · Webster’s 1913 — from the Wiktionary entry “sigma”, CC BY-SA 4.0. Details