E. Rossoni notes that Chiarion is native to the Rovigo area. As for the origin, he proposes several hypotheses: it could derive from the medieval name Claro, meaning "luminous"; or from nicknames related to place names such as Chiari, in the Brescia area, or Chiarone, in the Grosseto area. Rossoni also gathers the opinion of the scholar Olivieri, according to whom Chiarion could derive from the name of the Saracen character Clarione, peculiar to Carolingian onomastics.

F. De Laurentiis describes it as a Venetan derivative of the Latin clarus, which agrees in general terms with the etymological base noted by Rossoni.