TRIARTICULATE
Tri`ar*tic"u*late, a. Etym: [Pref. tri- + articulate.] (Zoöl.)
Defn: Having three joints.
TRIAS
Tri"as, n. Etym: [L., triad. See Triad.] (Geol.)
Defn: The formation situated between the Permian and Lias, and so named by the Germans, because consisting of three series of strata, which are called in German the Bunter sandstein, Muschelkalk, and Keuper.
TRIASSIC
Tri*as"sic, a. (Geol.)
Defn: Of the age of, or pertaining to, the Trias.
— n.
Defn: The Triassic formation.
TRIATIC
Tri*at"ic, a. (Naut.)
Defn: A term used in the phrase triatic stay. See under Stay.
TRIATOMIC Tri`a*tom"ic, a. Etym: [Pref. tri- + atomic.] (Chem.) (a) Having three atoms; — said of certain elements or radicals. (b) Having a valence of three; trivalent; sometimes, in a specific sense, having three hydroxyl groups, whether acid or basic; thus, glycerin, glyceric acid, and tartronic acid are each triatomic.