sinusoid vs undulation

sinusoid and undulation both are nouns.

Word	Noun	Adjective	Verb	Adverb
sinusoid	Yes	No	No	No
undulation	Yes	No	No	No

As nouns, undulation is a hypernym of sinusoid; that is, undulation is a word with a broader meaning than sinusoid:

Other hypernyms of sinusoid include wave.

sinusoid (noun)	undulation (noun)
tiny endothelium-lined passages for blood in the tissue of an organ	(physics) a movement up and down or back and forth
the curve of y=sin x	wavelike motion; a gentle rising and falling in the manner of waves
	an undulating curve