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.]WordNet (r) 3.0 (2006):
trisaccharide n 1: any of a variety of carbohydrates that yield three monosaccharide molecules on complete hydrolysis