Tri*sect"ed, a. (Bot.) Divided into three parts or segments by
incisions extending to the midrib or to the base; — said of leaves.
Tri*sec"tion (?), n. [Cf. F. trisection.] The division of a thing into
three parts, Specifically: (Geom.) the division of an angle into three
equal parts.
Tri*ser"al*ous (?), a. [Pref. tri- + sepal.] (Bot.) Having three
sepals, or calyx leaves.
{ Tri*se"ri*al (?), Tri*se"ri*ate (?), } a. [Pref. tri- + serial,
seriate.] (Bot.) Arranged in three vertical or spiral rows.
||Tris"mus (?), n. [NL., form Gr. &?; gnashing of the teeth.] (Med.)
||The lockjaw.
||
Tris*ni"trate (?), n. [Gr. &?; thrice + E. nitrate.] (Chem.) A nitrate
formed from three molecules of nitric acid; also, less properly,
applied to certain basic nitrates; as, trisnitrate of bismuth.
Tris*oc`ta*he"dron (?), n. [Gr. &?; thrice + FE. octahedron.]
(Crystallog.) A solid of the isometric system bounded by twenty-four
equal faces, three corresponding to each face of an octahedron.
Tetragonal trisoctahedron, a trisoctahedron each face of which is a
quadrilateral; called also trapezohedron and icositetrahedron. —
Trigonal trisoctahedron, a trisoctahedron each face of which is an
isosceles triangle.
{ Tri"spast (?), Tri*spas"ton (?), } n. [NL. trispaston, fr. Gr. &?;
drawn threefold; &?; (see Tri-) + &?; to draw.] (Mech.) A machine with
three pulleys which act together for raising great weights. Brande & C.
Tri*sper"mous (?), a. [Pref. tri- + Gr. &?; seed.] (Bot.) Containing
three seeds; three-seeded; as, a trispermous capsule.
Tri*splanch"nic (?), a. [Tri- + splanchnic.] (Anat.) Of or pertaining
to the three great splanchnic cavities, namely, that of the head, the
chest, and the abdomen; — applied to the sympathetic nervous system.
Trist (?), v. t. & i. [imp. Triste.] To trust. [Obs.] Chaucer.