Lecithin

[les-uh-thin] /ˈlɛs ə θɪn/

noun
1.
Biochemistry. any of a group of phospholipids, occurring in animal and plant tissues and egg yolk, composed of units of choline, phosphoric acid, fatty acids, and glycerol.
2.
a commercial form of this substance, obtained chiefly from soybeans, corn, and egg yolk, used in foods, cosmetics, and inks.
/ˈlɛsɪθɪn/
noun
1.
(biochem) any of a group of phospholipids that are found in many plant and animal tissues, esp egg yolk: used in making candles, cosmetics, and inks, and as an emulsifier and stabilizer in foods (E322) Systematic name phosphatidylcholine
n.

fatty substance found in the yolks of eggs (among other places), 1861, from French lécithine (coined 1850 by N.T. Gobley), from Greek lekithos “egg yolk,” + chemical suffix -ine (2). Greek lekithos is of unknown origin.

lecithin lec·i·thin (lěs’ə-thĭn)
n.
Any of a group of phospholipids that on hydrolysis yield two fatty acid molecules and a molecule each of glycerophosphoric acid and choline. They are found in nervous tissue, especially myelin sheaths and egg yolk, and in the plasma membrane of plant and animal cells.
lecithin
(lěs’ə-thĭn)
A fatty substance present in most plant and animal tissues that is an important structural part of cell membranes, particularly in nervous tissue. It consists of a mixture of diglycerides of fatty acids (especially linoleic, palmitic, stearic, and oleic acid) linked to a phosphoric acid ester. Lecithin is used commercially in foods, cosmetics, paints, and plastics for its ability to form emulsions.