circular saw vs sawing machine

circular saw and sawing machine both are nouns.

Word	Noun	Adjective	Verb	Adverb
circular saw	Yes	No	No	No
sawing machine	Yes	No	No	No

As nouns, sawing machine is a hypernym of circular saw; that is, sawing machine is a word with a broader meaning than circular saw:

circular saw: a power saw that has a steel disk with cutting teeth on the periphery; rotates on a spindle
sawing machine: a power tool for cutting wood

Other hypernyms of circular saw include power saw, saw.

circular saw (noun)	sawing machine (noun)
a power saw that has a steel disk with cutting teeth on the periphery; rotates on a spindle	a power tool for cutting wood