stare vs mug

stare and mug both are nouns.

Word	Noun	Adjective	Verb	Adverb
stare	Yes	No	Yes	No
mug	Yes	No	Yes	No

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

Other hyponyms of stare include outface, outstare, stare down, stargaze.

stare (noun)	mug (noun)
a fixed look with eyes open wide	with handle and usually cylindrical
	the human face (`kisser' and `smiler' and `mug' are informal terms for `face' and `phiz' is British)
	a person who is gullible and easy to take advantage of
	the quantity that can be held in a mug

stare (verb)	mug (verb)
fixate one's eyes	To stare awkwardly
look at with fixed eyes	rob at gunpoint or with the threat of violence