sigma

[ sig-muh ]

noun
  1. the 18th letter of the Greek alphabet: Σ, σ, ς.

  2. the consonant sound represented by this letter.

Origin of sigma

1
First recorded in 1600–10; from Latin, from Greek sígma

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2024

How to use sigma in a sentence

  • The little pair southeast of Aldebaran, called the Sigmas, is also a beautiful object.

    Astronomy with an Opera-glass | Garrett Putman Serviss
  • The latter, seeing the Sigmas on the shields and taking them to be "Sicyonians," had not the slightest fear.

    Hellenica | Xenophon

British Dictionary definitions for sigma

sigma

/ (ˈsɪɡmə) /


noun
  1. the 18th letter in the Greek alphabet (Σ, σ, or, when final, ς), a consonant, transliterated as S

  2. maths the symbol Σ, indicating summation of the numbers or quantities indicated

Origin of sigma

1
Greek, of Semitic origin; related to Hebrew samekh

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Scientific definitions for sigma

sigma

[ sĭg ]


  1. A sigma baryon.

The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.