rowing boat vs dinghy

rowing boat and dinghy both are nouns.

Word	Noun	Adjective	Verb	Adverb
rowing boat	Yes	No	No	No
dinghy	Yes	No	No	No

As nouns, dinghy is a hypernym of rowing boat; that is, dinghy is a word with a broader meaning than rowing boat:

rowing boat: a rowboat
dinghy: a small boat of shallow draft with cross thwarts for seats and rowlocks for oars with which it is propelled

Other hypernyms of rowing boat include dory, rowboat.

rowing boat (noun)	dinghy (noun)
a rowboat	a small boat of shallow draft with cross thwarts for seats and rowlocks for oars with which it is propelled