sperm vs sperm cell

sperm and sperm cell both are nouns.

Word	Noun	Adjective	Verb	Adverb
sperm	Yes	No	No	No
sperm cell	Yes	No	No	No

As nouns, sperm and sperm cell are synonyms defined as:

Other synonyms of sperm include spermatozoan, spermatozoon.

sperm (noun)	sperm cell (noun)
the male reproductive cell; the male gamete	the male reproductive cell; the male gamete