The Collaborative International Dictionary
Trichotomous
Trichotomous \Tri*chot"o*mous\, a. [See Trichotomy.]
Divided into three parts, or into threes; three-forked; as, a
trichotomous stem.
--Martyn.
Wiktionary
trichotomous
a. Divided into three parts, or into threes; forking three ways.
Usage examples of "trichotomous".
She was in direct contact with the enemy and her visual evidence seems to bear out that theory of yours regarding the trichotomous pattern of the aliens' behavior.