- male sexual activityIn the 19th century it meant copulation, when it was not thought proper for women to relish the activity:While you were at your beastliness ... (Fraser, 1971, writing in archaic style)Now it means masturbation, which is hardly fair, as most animals don't masturbate:... the detrimental effects on sportsmen of masturbation, referred to in the sermon as beastliness. (Sharpe, 1982)
How not to say what you mean: A dictionary of euphemisms. R. W. Holder. 2014.