rotary motion vs rotation

rotary motion and rotation both are nouns.

Word	Noun	Adjective	Verb	Adverb
rotary motion	Yes	No	No	No
rotation	Yes	No	No	No

As nouns, rotary motion and rotation are synonyms defined as:

rotary motion (noun)	rotation (noun)
the act of rotating as if on an axis	the act of rotating as if on an axis
	a planned recurrent sequence (of crops or personnel etc.)
	a single complete turn (axial or orbital)
	(mathematics) a transformation in which the coordinate axes are rotated by a fixed angle about the origin