- bleach (v.)
- Old English blæcan "bleach, whiten," from Proto-Germanic *blaikjan "to make white" (cf. Old Saxon blek, Old Norse bleikr, Dutch bleek, Old High German bleih, German bleich "pale;" Old Norse bleikja, Dutch bleken, German bleichen "to bleach"), from PIE root *bhel- (1) "to shine, flash, burn" (cf. Sanskrit bhrajate "shines;" Greek phlegein "to burn;" Latin flamma "flame," fulmen "lightning," fulgere "to shine, flash," flagrare "to burn;" Old Church Slavonic belu "white;" Lithuanian balnas "pale"). The same root probably produced black; perhaps because both black and white are colorless, or because both are associated with burning. Related: Bleached; bleaching.
- bleach (n.)
- "act of bleaching," 1887; "a bleaching agent," 1898, probably directly from bleach (v.). The Old English noun blæce meant "leprosy;" Late Old English also had blæco "paleness," and Middle English had blech "whitening or bleaching agent."