Sigma (disambiguation)

Sigma (Σ or σ, word-final lowercase ς) is the 18th letter of the Greek alphabet.

Sigma may also refer to:

Companies and organizations

Sigma AB, a Swedish IT consultancy company
Sigma Alimentos, multinational food processing and distribution company
Sigma Corporation, a Japanese camera and lens manufacturer
Sigma Designs, Inc., a US semiconductor manufacturer
Sigma Healthcare, an Australian pharmaceutical company
Sigma Motor Corporation, a defunct South African motor vehicle assembler and manufacturer
Sigma Motors, a Pakistani assembler of Land Rovers
Sigma Sigma Sigma (Tri-Sigma), an American women's sorority centered on education & scholarship
Sigma Sport, a German manufacturer of electronic sports equipment
Sigma TV, a television channel in Cyprus
Sigma (operations research), a company founded in the UK in 1961
SIGMA (verification service), Nielsen Media Research's tracking system for videos
Sigma-Aldrich, an American chemical company
Telkomsigma or Sigma Cipta Caraka, an Indonesian IT company
Sigma Guitars, a guitar manufacturing brand

Ood Sigma, a fictional character from the Doctor Who series
Space City Sigma, a 1980s Indian science fiction TV series
Sigma, a fictional character from the anime Tweeny Witches
Sigma Society, a fictional Mensa-type club, appearing in the third episode of Columbo sixth season
Sigma, a fictional character from the Bungo Stray Dogs manga and anime series

Sigma, Capiz, a municipality in the Philippines
Sigma, Lee County, Virginia, an unincorporated community in the United States
Sığma, Sarayköy, a neighbourhood of the municipality and district of Sarayköy, Denizli Province, Turkey
The Sigma Plan, to raise the dikes of the Scheldt River in Belgium

GM Sigma platform, an automobile platform
Mitsubishi Sigma, a model name used for various automobiles produced by Mitsubishi
Chrysler Sigma, a version of the Mitsubishi Galant sold in Australia
Ferrari Sigma, also known as the Pininfarina Sigma, a Formula 1 show car
SDS Sigma series of computers from Scientific Data Systems
Sigma (sailplane), an experimental glider developed in Britain from 1966
Six Sigma quality management program
Smith & Wesson Sigma, a firearm

σ, sigma bond in chemistry
σ, sigma factor of RNA polymerase in biology
σ, Stefan–Boltzmann constant of radiation in physics
σ, stress (mechanics), the force per unit area applied by internal forces of a material
σ, the electronic substituent constant for activation of substituted arenes in the Hammett equation
σ, a measure of a material's electrical conductivity ability
Cross section σ in physics
Pauli matrices in quantum physics
Sigma baryon in particle physics
Sigma receptor, a neural receptor
Surface charge density in classical electromagnetism
Sigma, a Greek letter used in Bayer designations for naming stars, in astronomy. Notable examples include:

Sigma (Mega Man X), the villain of the Mega Man X series
Sigma (Overwatch), a hero from Overwatch
Ninja Gaiden Sigma, a video game
Sigma, a character in the BioShock 2 video game universe
Sigma Harmonics, a video game
Sigma Klim, a major character and protagonist in the Zero Escape video game series
Sigma, a team on the Dota 2 online video game