commentary vs Midrash

commentary and Midrash both are nouns.

Word	Noun	Adjective	Verb	Adverb
commentary	Yes	No	No	No
Midrash	Yes	No	No	No

As nouns, Midrash is a hyponym of commentary; that is, Midrash is a word with a more specific, narrower meaning than commentary:

commentary: a written explanation or criticism or illustration that is added to a book or other textual material
Midrash: (Judaism) an ancient commentary on part of the Hebrew scriptures that is based on Jewish methods of interpretation and attached to the biblical text

Other hyponyms of commentary include annotation, notation, note.

commentary (noun)	Midrash (noun)
a written explanation or criticism or illustration that is added to a book or other textual material	(Judaism) an ancient commentary on part of the Hebrew scriptures that is based on Jewish methods of interpretation and attached to the biblical text