freebieyoudaoicibaDictYouDict[freebie 词源字典]
also freeby, 1942 (adj.) "for nothing, without charge;" 1946 (n.) "something given for free;" perhaps as early as 1900; formed "Arbitrarily" [OED] from free (adj.). Compare newbie, rudesby.[freebie etymology, freebie origin, 英语词源]