Loading word page…
Updated June 2026
The Greek letter σ, used in mathematics and science to represent summation.
“The formula uses sigma to indicate the sum of all values.”
/ˈsɪɡmə/
sig·ma
Uncommon word with vowel-consonant pattern.
Worth 8 points; good for using uncommon letters.
Change a single letter of “sigma” to make these 5-letter words — useful for Wordle and crossword clues.
6-letter words you can spell by adding one letter to “sigma”.
Look up sigma in an authoritative dictionary for full definitions, pronunciation, and etymology.
Download Word Challenge for unlimited word puzzles, a fresh Daily Challenge, and head-to-head multiplayer. Guess the hidden word in six tries or fewer!