throwaway (adj.)youdaoicibaDictYouDict[throwaway 词源字典]
also throw-away, 1901 in reference to very low prices; by 1903 in reference to printed material meant to be read once then tossed, and to wasted votes; with reference to disposable consumer goods, attested from 1969. From the verbal phrase, attested from late 14c. in the sense "reject, cast from oneself," from throw (v.) + away (adv.). More literal meaning of "dispose of as useless, release from one's possession as unneeded" is first recorded 1520s. Throw-away society attested from 1967.[throwaway etymology, throwaway origin, 英语词源]