cookery vs stewing

cookery and stewing both are nouns.

Word	Noun	Adjective	Verb	Adverb
cookery	Yes	No	No	No
stewing	Yes	No	No	No

As nouns, stewing is a hyponym of cookery; that is, stewing is a word with a more specific, narrower meaning than cookery:

cookery: the act of preparing something (as food) by the application of heat
stewing: cooking in a liquid that has been brought to a boil

cookery (noun)	stewing (noun)
the act of preparing something (as food) by the application of heat	cooking in a liquid that has been brought to a boil
	an extreme state of worry and agitation