walk-on vs histrion

walk-on and histrion both are nouns.

Word	Noun	Adjective	Verb	Adverb
walk-on	Yes	Yes	No	No
histrion	Yes	No	No	No

As nouns, histrion is a hypernym of walk-on; that is, histrion is a word with a broader meaning than walk-on:

Other hypernyms of walk-on include actor, player, role player, thespian.

walk-on (noun)	histrion (noun)
plays a small part in a dramatic production	a theatrical performer

walk-on (adjective)	histrion (adjective)
not capable of or especially not involving speech or spoken lines