commendation vs subject matter

commendation and subject matter both are nouns.

Word	Noun	Adjective	Verb	Adverb
commendation	Yes	No	No	No
subject matter	Yes	No	No	No

As nouns, subject matter is a hypernym of commendation; that is, subject matter is a word with a broader meaning than commendation:

Other hypernyms of commendation include content, message, substance.

commendation (noun)	subject matter (noun)
an official award (as for bravery or service) usually given as formal public statement	content communicating a message; what something is about
a message expressing a favorable opinion