WWordGenerator.org GeneratorsWord ListsBlogAboutGenerate a word Home / S / sigma sigma noun 5 letters Scrabble 8 WWF 10 Definitions noun the 18th letter of the Greek alphabet Look “sigma” up elsewhere Wiktionary ↗ Merriam-Webster ↗ Etymonline ↗ Dictionary.com ↗ Want another word?Spin the dictionary for a fresh one. Generate a word →