trisaccharide

from WordNet (r) 3.0 (2006)

trisaccharide
    n 1: any of a variety of carbohydrates that yield three
         monosaccharide molecules on complete hydrolysis

from The Collaborative International Dictionary of English v.0.48

Trisaccharide \Tri*sac"cha*ride\, n. Also -rid \-rid\ (Chem.)
   A complex sugar, as raffinose, yielding by hydrolysis three
   simple sugar molecules.
   [Webster 1913 Suppl.]