backsaw vs hand saw

backsaw and hand saw both are nouns.

Word	Noun	Adjective	Verb	Adverb
backsaw	Yes	No	No	No
hand saw	Yes	No	No	No

As nouns, hand saw is a hypernym of backsaw; that is, hand saw is a word with a broader meaning than backsaw:

backsaw: a handsaw that is stiffened by metal reinforcement along the upper edge
hand saw: a saw used with one hand for cutting wood

Other hypernyms of backsaw include carpenter's saw, handsaw.

backsaw (noun)	hand saw (noun)
a handsaw that is stiffened by metal reinforcement along the upper edge	a saw used with one hand for cutting wood