A unit of measurement for determining the length and girth of an erect penis. Used exclusively by men (usually but not always gay men) in online dating or chat profiles, the unit, while not uniform, often corresponds roughly to 1.5 American or English system inches. For example a standard 6 inch long penis becomes 9 AOL inches, etc., though the "average" AOL inch length appears to be between 8-9. Despite the name, AOL inches are now used universally online, not just on AOL anymore.
36, 6'3", 190 lbs., br, br, buzzed, stache, regular guy here, 8.5"c thick (NOT AOL inches).