intermezzo vs opus

intermezzo and opus both are nouns.

Word	Noun	Adjective	Verb	Adverb
intermezzo	Yes	No	No	No
opus	Yes	No	No	No

As nouns, opus is a hypernym of intermezzo; that is, opus is a word with a broader meaning than intermezzo:

intermezzo: a short piece of instrumental music composed for performance between acts of a drama or opera
opus: a musical work that has been created

Other hypernyms of intermezzo include composition, musical composition, piece, piece of music.

intermezzo (noun)	opus (noun)
a brief show (music or dance etc) inserted between the sections of a longer performance	a musical work that has been created
a short piece of instrumental music composed for performance between acts of a drama or opera
a short movement coming between the major sections of a symphony