leaf blade vs leafage

leaf blade and leafage both are nouns.

Word	Noun	Adjective	Verb	Adverb
leaf blade	Yes	No	No	No
leafage	Yes	No	No	No

As nouns, leafage is a hypernym of leaf blade; that is, leafage is a word with a broader meaning than leaf blade:

leaf blade: especially a leaf of grass or the broad portion of a leaf as distinct from the petiole
leafage: the main organ of photosynthesis and transpiration in higher plants

Other hypernyms of leaf blade include foliage, leaf.

leaf blade (noun)	leafage (noun)
especially a leaf of grass or the broad portion of a leaf as distinct from the petiole	the main organ of photosynthesis and transpiration in higher plants