flavor vs zest

flavor and zest both are nouns.

Word	Noun	Adjective	Verb	Adverb
flavor	Yes	No	Yes	No
zest	Yes	No	Yes	No

As verbs, zest is a hyponym of flavor; that is, zest is a word with a more specific, narrower meaning than flavor:

Other hyponyms of flavor include sauce, curry, resinate, spice, spice up, savor, savour, salt.

flavor (noun)	zest (noun)
the taste experience when a savoury condiment is taken into the mouth	a tart spicy quality
(physics) the six kinds of quarks	vigorous and enthusiastic enjoyment
the general atmosphere of a place or situation and the effect that it has on people

flavor (verb)	zest (verb)
lend flavor to	add herbs or spices to