stearin

UK: /ˈstɪərɪn/ US: (stē′ə rin, stēr′in)

WordReference Random House Unabridged Dictionary of American English © 2025

ste•a•rin  (stē′ə rin, stēr′in), n. 

1. Biochemistry, Chemistry [Chem.] any of the three glyceryl esters of stearic acid, esp. C₃H₅(C₁₈H₃₅O₂)₃, a soft, white, odorless solid found in many natural fats.
2. Chemistry the crude commercial form of stearic acid, used chiefly in the manufacture of candles.

Also, ste•a•rine  (stē′ər in, -ə rēn′, stēr′in). 

• Greek stéar fat, grease + French -ine -ine²; see -in²
• French stéarine
• 1810–20

Collins Concise English Dictionary © HarperCollins Publishers::

stearin, stearine / ˈstɪərɪn/ noun

1. Also called: tristearin a colourless crystalline ester of glycerol and stearic acid, present in fats and used in soap and candles; glycerol tristearate; glycerol trioctadecanoate. Formula: (C₁₇H₃₅COO)₃C₃H₅
2. another name for stearic acid, esp a commercial grade containing other fatty acids
3. fat in its solid form

Etymology: 19th Century: from French stéarine, from Greek stear fat, tallow + -in