give-away
n.
also giveaway, "act of giving away," 1872, from verbal phrase give away, c.1400 (of brides from 1719); see give, v. + away, adv.. The phrase in the meaning "to betray, expose, reveal" is from 1878, originally U.S. slang. Hence also Related: give-away (n.) "inadvertent betrayal or revelation" (1882).