slaveholder vs slave owner

slaveholder and slave owner both are nouns.

Word	Noun	Adjective	Verb	Adverb
slaveholder	Yes	No	No	No
slave owner	Yes	No	No	No

As nouns, slaveholder and slave owner are synonyms defined as:

Other synonyms of slaveholder include slaver.

slaveholder (noun)	slave owner (noun)
someone who holds slaves	someone who holds slaves