sculler vs rower

sculler and rower both are nouns.

Word	Noun	Adjective	Verb	Adverb
sculler	Yes	No	No	No
rower	Yes	No	No	No

As nouns, rower is a hypernym of sculler; that is, rower is a word with a broader meaning than sculler:

sculler: someone who sculls (moves a long oar pivoted on the back of the boat to propel the boat forward)
rower: someone who rows a boat

sculler (noun)	rower (noun)
someone who sculls (moves a long oar pivoted on the back of the boat to propel the boat forward)	someone who rows a boat