authorisation vs muscle

authorisation and muscle both are nouns.

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

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

authorisation: the power or right to give orders or make decisions
muscle: authority or power or force (especially when used in a coercive way)

Other hyponyms of authorisation include power of appointment, carte blanche, command, imperium, lordship, sovereignty.

authorisation (noun)	muscle (noun)
the act of conferring legality or sanction or formal warrant	possessing muscular strength
the power or right to give orders or make decisions	authority or power or force (especially when used in a coercive way)
official permission or approval	one of the contractile organs of the body
a document giving an official instruction or command	animal tissue consisting predominantly of contractile cells
	a bully employed as a thug or bodyguard

authorisation (verb)	muscle (verb)
	make one's way by force