sigma

[ sig-muh ]

/ ˈsɪg mə /

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noun

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

the consonant sound represented by this letter.

QUIZ

CAN YOU ANSWER THESE COMMON GRAMMAR DEBATES?

There are grammar debates that never die; and the ones highlighted in the questions in this quiz are sure to rile everyone up once again. Do you know how to answer the questions that cause some of the greatest grammar debates?

Question 1 of 7

Which sentence is correct?

His boss, whom he admires, is waiting to meet with him about the big project.

His boss, who he admires, is waiting to meet with him about the big project.

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Origin of sigma

1600–10; <Latin <Greek sígma

Words nearby sigma

SIGINT, Sigismund, Sigismund II, sigla, siglos, sigma, sigma baryon, sigma particle, sigmate, sigmatism, sigmoid

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

How to use sigma in a sentence

The drugs either targeted the sigma receptors or they stopped the virus from growing.
Why it’s still so hard to find treatments for early COVID-19|Tina Hesman Saey|July 27, 2021|Science News
SigMa members held demonstrations at MAL’s host hotel and always saw a bump in attendance from visitors in town for the event.
SigMa DC to suspend operations on Sept. 30|Ed Gunts|September 24, 2020|Washington Blade
Lohse rushes Sigma Alpha Epsilon, gets a bid, endures pledge term, and then submits to the dehumanizing rigors of Hell Night.
An Ivy League Frat Boy’s Shallow Repentance|Stefan Beck|November 24, 2014|DAILY BEAST
Pledging, also known as initiation, will now be abolished by Sigma Alpha Epsilon nationally across its 240 chapters.
Deadly Frat Rituals Are Banned Thanks to Technology|Joe Concha|March 10, 2014|DAILY BEAST

For example, what business has the letter rho in the word katoptron, or the letter sigma in the word sphigx?
Cratylus|Plato
All of them wore, in addition to their temple knives, holstered sigma-ray needlers.
Temple Trouble|Henry Beam Piper
He drew his hand from under the left side of the senseless man's robe and held up a sigma-ray needler.
Temple Trouble|Henry Beam Piper
Sigma, sig′ma, n. the Greek letter corresponding to our s—written Σ (capital), σ (small initial) or ς (small final).
Chambers's Twentieth Century Dictionary (part 4 of 4: S-Z and supplements)|Various
It is to be observed that the Grecians in foreign words continually omitted the Nu final, and substituted a Sigma.
A New System; or, an Analysis of Antient Mythology. Volume I.|Jacob Bryant

British Dictionary definitions for sigma

sigma

/ (ˈsɪɡmə) /

noun

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

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

Word Origin for sigma

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′mə ]

A sigma baryon.