(1):

(n.) An eldery man; - used chiefly as a kindly or familiar appellation, esp. (Southern U. S.) for a worthy old negro; as, "Uncle Remus."

(2):

(n.) A pawnbroker.

(3):

(n.) The brother of one's father or mother; also applied to an aunt's husband; - the correlative of aunt in sex, and of nephew and niece in relationship.