whiten

name

1. A surname.

verb

Etymology: 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”).

1. (To cause) to become white or whiter; to bleach or blanch.

   “Age had whitened his hair.”

   “The trees in spring whiten with blossoms.”

2. To increase the security of an iterated block cipher by steps that combine the data with portions of the key.
3. To normalize data so that the covariance matrix becomes the identity matrix; i.e., to remove correlations so each variable has unit variance.