turtle vs polo-neck

turtle and polo-neck both are nouns.

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

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

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

Other synonyms of turtle include turtleneck.

turtle (noun)	polo-neck (noun)
any of various aquatic and land reptiles having a bony shell and flipper-like limbs for swimming	a sweater or jersey with a high close-fitting collar
a sweater or jersey with a high close-fitting collar

turtle (verb)	polo-neck (verb)
hunt for turtles, especially as an occupation
overturn accidentally