second fiddle vs subsidiary

second fiddle and subsidiary both are nouns.

Word	Noun	Adjective	Verb	Adverb
second fiddle	Yes	No	No	No
subsidiary	Yes	Yes	No	No

As nouns, subsidiary is a hypernym of second fiddle; that is, subsidiary is a word with a broader meaning than second fiddle:

second fiddle: someone who serves in a subordinate capacity or plays a secondary role
subsidiary: an assistant subject to the authority or control of another

Other hypernyms of second fiddle include foot soldier, subordinate, underling.

second fiddle (noun)	subsidiary (noun)
a secondary role or function	a company that is completely controlled by another company
someone who serves in a subordinate capacity or plays a secondary role	an assistant subject to the authority or control of another

second fiddle (adjective)	subsidiary (adjective)
	functioning in a supporting capacity