(especially in the Southern US, parts of Britain and Asia) An affectionate term for a man of an older generation than oneself, especially a friend of one's parents, by means of fictive kin.
(Southern US, slang, archaic) An older male African-American person.
“If he lives in a society which has established unclehood as a centrally significant institution (not ours, to be sure, but most matrilineal societies)...”