polo-neck vs turtleneck

polo-neck and turtleneck both are nouns.

Word	Noun	Adjective	Verb	Adverb
polo-neck	Yes	No	No	No
turtleneck	Yes	No	No	No

As nouns, polo-neck and turtleneck are synonyms defined as:

polo-neck and turtleneck: a sweater or jersey with a high close-fitting collar

Other synonyms of polo-neck include turtle.

polo-neck (noun)	turtleneck (noun)
a sweater or jersey with a high close-fitting collar	a sweater or jersey with a high close-fitting collar