sorrower vs mourner

sorrower and mourner both are nouns.

Word	Noun	Adjective	Verb	Adverb
sorrower	Yes	No	No	No
mourner	Yes	No	No	No

As nouns, sorrower and mourner are synonyms defined as:

sorrower and mourner: a person who is feeling grief (as grieving over someone who has died)

Other synonyms of sorrower include griever, lamenter.

sorrower (noun)	mourner (noun)
a person who is feeling grief (as grieving over someone who has died)	a person who is feeling grief (as grieving over someone who has died)