B. Zuanella records this surname as extinct in the comune of Grimacco, in Friuli (Udine area). Since it is not documented in the territory of the Republic of Slovenia, Zuanella considers it of Romance (Friulian) origin and derives it, with reservation, from the Friulian noun muse —which means "face, countenance, muzzle" (the equivalent of the Slovene gobec)— with the suffix -in. In origin it would have functioned as a nickname to designate a person of pleasant and agreeable appearance.

E. Rossoni agrees on the etymological base, noting that the surname would derive from a diminutive form of the Friulian muse, used in an affectionate sense to allude to a pretty or agreeable face. Rossoni places it as proper to the Udine area, in Friuli.