bully vs muscle

bully and muscle both are nouns.

Word	Noun	Adjective	Verb	Adverb
bully	Yes	Yes	Yes	No
muscle	Yes	No	Yes	No

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

Other hyponyms of bully include bullyboy, muscleman, skin, skinhead, plug-ugly, tough guy.

bully (noun)	muscle (noun)
a cruel and brutal fellow	possessing muscular strength
a hired thug	authority or power or force (especially when used in a coercive way)
	one of the contractile organs of the body
	animal tissue consisting predominantly of contractile cells
	a bully employed as a thug or bodyguard

bully (adjective)	muscle (adjective)
excellent

bully (verb)	muscle (verb)
discourage or frighten with threats or a domineering manner; intimidate	make one's way by force
be bossy towards