(Tri*que"tral) a. Triquetrous.
(Tri*que"trous) a. [L. triquetrus.] Three sided, the sides being plane or concave; having
three salient angles or edges; trigonal.
(Tri*que"trum) n.; pl. Triquetra [NL.] (Anat.) One of the bones of the carpus; the cuneiform.
See Cuneiform (b).
(Tri*ra"di*ate Tri*ra"di*a`ted) , a. [Pref. tri- + radiate.] Having three rays.
(Tri`rec*tan"gu*lar) a. [Pref. tri- + rectangular.] (Spherical Trig.) Having three right
angles. See Triquadrantal.
(Tri"reme) n. [L. triremis; tri- (see Tri-) + remus an oar, akin to E. row. See Row to propel
with an oar.] (Class. Antiq.) An ancient galley or vessel with tree banks, or tiers, of oars.
(Tri`rhom*boid"al) a. [Pref. tri- + rhomboidal.] Having three rhombic faces or sides.
(Tri*sac`ra*men*ta"ri*an) n. [Pref. tri- + sacramentarian.] (Eccl.) One who recognizes
three sacraments, and no more; namely, baptism, the Lord's Supper, and penance. See Sacrament.
(||Tris*ag"i*on) n. [NL., fr. Gr. thrice holy; thrice + holy.] (Eccl.) An ancient anthem, usually
known by its Latin name tersanctus.See Tersanctus.
(Tri*sect") v. t. [imp. & p. p. Trisected; p. pr. & vb. n. Trisecting.] [Pref. tri- + L. sectus, p.
p. of secare to cut. See Section.]
1. To cut or divide into three parts.
2. (Geom.) To cut or divide into three equal parts.
(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
(||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.
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
(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.
(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.