Defn: Proved; tested; faithful; trustworthy; as, a tried friend.
TRIEDRAL
Tri*e"dral, a.
Defn: See Trihedral.
TRIENNIAL Tri*en"ni*al, a. Etym: [L. triennium the space of three years; tri- (see Tri-) + annus year. See Annual.]
1. Continuing three years; as, triennial parliaments; a triennial reign. Howell.
2. Happening, coming about, or appearing once in every three years; as, triennial elections; a triennial catalogue; a triennial visitation. T. Warton.
TRIENNIAL
Tri*en"ni*al, n.
Defn: Something which takes place or appears once in three years.
TRIENNIALLY
Tri*en"ni*al*ly, adv.
Defn: Once in three years.