fem. proper name; the first element is Breton gwenn "white" (source also of Welsh gwyn, Old Irish find, Gaelic fionn, Gaulish vindo- "white, shining," literally "visible"), from nasalized form of PIE root *weid- "to see."
fem. proper name, from Italian, fem. of bianco "white," which is from Germanic (see blank (adj.)). A doublet of French Blanche, which also is from Germanic, and compare Gwen, which means the same thing.
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<a href="https://www.etymonline.com/word/Gwen">Etymology of Gwen by etymonline</a>
Harper, D. (n.d.). Etymology of Gwen. Online Etymology Dictionary. Retrieved $(datetime), from https://www.etymonline.com/word/Gwen