rod cell vs retinal rod

rod cell and retinal rod both are nouns.

Word	Noun	Adjective	Verb	Adverb
rod cell	Yes	No	No	No
retinal rod	Yes	No	No	No

As nouns, rod cell and retinal rod are synonyms defined as:

rod cell and retinal rod: a visual receptor cell that is sensitive to dim light

Other synonyms of rod cell include rod.

rod cell (noun)	retinal rod (noun)
a visual receptor cell that is sensitive to dim light	a visual receptor cell that is sensitive to dim light