Origin of whitenMiddle English whitnen from Old Norse hvitna from hvitr, white
tr. & intr.v.whit·ened, whit·en·ing, whit·ens
(third-person singular simple present whitens, present participle whitening, simple past and past participle whitened)
From Middle English whitenen, whitnen, from Old Norse hvÃtna (“to whiten"), from Proto-Germanic *hwÄ«tnÅnÄ… (“to whiten, become white"), from Proto-Indo-European *kwind-, *kwint- (“bright"), equivalent to white +"Ž -en. Cognate with Icelandic hvÃtna (“to whiten"), Swedish vitna, hvitna (“to whiten"), Danish hvidne (“to whiten"). Compare Old English hwÄ«tian (“to whiten, become white, be white, make white").