Etymology Middle English and French "buffe" meaning buffalo. noun undyed leather from the skin of buffalo or similar animals. a tool, often one covered with buff leather, used for polishing. Colloquial: a person who is very interested in a particular subject. "He's a history buff." Colloquial bare skin. "He sleeps in the buff." a brownish yellow colour. a military coat made of buff leather. verb to polish and make shiny adjective of the color of buff leather, a brownish yellow. Related words See Appendix:Colours