In Irish finn means “fair, bright, white, lustrous, light-hued” (MacKillop: 226), and the Welsh gwyn is similar in meaning, with overtones of sacredness. Similarly, the Gaulish god, Vindonnus, gets his name from a root meaning either “clear light” (Green: 32) or “white, blessed” (Deo Mercurio). Coming at it from another direction, Daithai O hOgain has linked Finn/Vind with the Germanic find and Latin vid, words connected to sight and discovery (208).
From this it has been a short step to assuming a god, *Vindos, lying behind these various figures. However, like the “theoretical goddess” Rigantona, the names is a linguistic construct, and we have no evidence of a cult of Vindos.