side dish vs dish

side dish and dish both are nouns.

Word	Noun	Adjective	Verb	Adverb
side dish	Yes	No	No	No
dish	Yes	No	Yes	No

As nouns, dish is a hypernym of side dish; that is, dish is a word with a broader meaning than side dish:

side dish (noun)	dish (noun)
a dish that is served with, but is subordinate to, a main course	an activity that you like or at which you are superior
	a piece of dishware normally used as a container for holding or serving food
	directional antenna consisting of a parabolic reflector for microwave or radio frequency radiation
	a particular item of prepared food
	a very attractive or seductive looking woman
	the quantity that a dish will hold

side dish (verb)	dish (verb)
	make concave; shape like a dish
	provide (usually but not necessarily food)