roving frame vs fly frame

roving frame and fly frame both are nouns.

Word	Noun	Adjective	Verb	Adverb
roving frame	Yes	No	No	No
fly frame	Yes	No	No	No

As nouns, roving frame and fly frame are synonyms defined as:

roving frame and fly frame: a textile machine that transforms the drawn sliver into roving.

Other synonyms of roving frame include simplex machine, speed frame.

roving frame (noun)	fly frame (noun)
a textile machine that transforms the drawn sliver into roving.	a textile machine that transforms the drawn sliver into roving.