means A small gland in male anatomy, sitting just below the bladder, that produces fluid for semen and tends to enlarge with age.

from From the Greek 'prostates,' meaning 'one who stands before' (pro-, 'before,' plus 'histanai,' 'to stand') — literally the guard or protector posted at the front, named for its position standing before the bladder. Worth noting: it's often confused with 'prostrate' (lying face-down), an unrelated word from Latin 'prosternere,' 'to throw down.'