lecithin vs emulsifier

lecithin and emulsifier both are nouns.

Word	Noun	Adjective	Verb	Adverb
lecithin	Yes	No	No	No
emulsifier	Yes	No	No	No

As nouns, emulsifier is a hypernym of lecithin; that is, emulsifier is a word with a broader meaning than lecithin:

lecithin: a yellow phospholipid essential for the metabolism of fats; found in egg yolk and in many plant and animal cells; used commercially as an emulsifier
emulsifier: a surface-active agent that promotes the formation of an emulsion

Other hypernyms of lecithin include phospholipid.

lecithin (noun)	emulsifier (noun)
a yellow phospholipid essential for the metabolism of fats; found in egg yolk and in many plant and animal cells; used commercially as an emulsifier	a surface-active agent that promotes the formation of an emulsion