wash-out (n.)youdaoicibaDictYouDict[wash-out 词源字典]
also washout, 1877, "act of washing out" (a drain, etc.), from verbal phrase; see wash (v.) + out (adv.). From 1873 as "excavation of a roadbed, etc., by erosion" is from 1873. Meaning "a disappointing failure" is from 1902, from verbal phrase wash out "obliterate, cancel" (something written in ink), attested from 1570s. Hence also the colloquial sense of "to call off (an event) due to bad weather, etc." (1917). Of colored material, washed-out "faded" is from 1837.[wash-out etymology, wash-out origin, 英语词源]