Source : Webster's Revised Unabridged Dictionary (1913)

Mantelletta \Man`tel*let"ta\, n. [It. mantelletta. See
   {Mantelet}.] (R. C. Ch.)
   A silk or woolen vestment without sleeves worn by cardinals,
   bishops, abbots, and the prelates of the Roman court. It has
   a low collar, is fastened in front, and reaches almost to the
   knees.