season vs zest

season and zest both are nouns.

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

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

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

season (noun)	zest (noun)
one of the natural periods into which the year is divided by the equinoxes and solstices or atmospheric conditions	a tart spicy quality
a recurrent time marked by major holidays	vigorous and enthusiastic enjoyment
a period of the year marked by special events or activities in some field

season (verb)	zest (verb)
make healthy	add herbs or spices to
make more temperate, acceptable, or suitable by adding something else
lend flavor to