passage vs opus

passage and opus both are nouns.

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

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

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

passage (noun)	opus (noun)
a journey usually by ship	a musical work that has been created
the passing of a law by a legislative body
the act of passing something to another person
the act of passing from one state or place to the next
a bodily reaction of changing from one place or stage to another
a way through or along which someone or something may pass
a path or channel or duct through or along which something may pass
a section of text; particularly a section of medium length
a short section of a musical composition
the motion of one object relative to another