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 hvítna (“to whiten”), from Proto-Germanic *hwītnōną (“to whiten, become white”), from Proto-Indo-European *kwind-, *kwint- (“bright”), equivalent to white + -en. Cognate with Icelandic hvítna (“to whiten”), Swedish vitna, hvitna (“to whiten”), Danish hvidne (“to whiten”). Compare Old English hwītian (“to whiten, become white, be white, make white”).