pitsaw vs lumberman's saw

pitsaw and lumberman's saw both are nouns.

Word	Noun	Adjective	Verb	Adverb
pitsaw	Yes	No	No	No
lumberman's saw	Yes	No	No	No

As nouns, lumberman's saw is a hypernym of pitsaw; that is, lumberman's saw is a word with a broader meaning than pitsaw:

pitsaw: a large two-handed saw formerly used to cut logs into planks; one man stood above the log and the other in a pit below
lumberman's saw: a saw with handles at both ends; intended for use by two people

Other hypernyms of pitsaw include two-handed saw, two-man saw, whipsaw.

pitsaw (noun)	lumberman's saw (noun)
a large two-handed saw formerly used to cut logs into planks; one man stood above the log and the other in a pit below	a saw with handles at both ends; intended for use by two people