a. [ L. attrahens, p. pr. of attrahere. See Attract, v. t. ] Attracting; drawing; attractive. [ 1913 Webster ]

n. 1. That which attracts, as a magnet. [ 1913 Webster ]

The motion of the steel to its attrahent. Glanvill. [ 1913 Webster ]

2. (Med.) A substance which, by irritating the surface, excites action in the part to which it is applied, as a blister, an epispastic, a sinapism. [ 1913 Webster ]

a. [ L. contrahens, p. pr. See Contract. ] Entering into covenant; contracting; as, contrahent parties. [ Obs. ] Mede. [ 1913 Webster ]

n. [ Gr. &unr_; twenty + &unr_;, combining form of &unr_; four + &unr_; seat, base. ] (Crystallog.) A twenty-four-sided solid; a tetragonal trisoctahedron or trapezohedron. [ 1913 Webster ]

n. [ L. subtrahendus that is to be subtracted, p.fut.pess. of subtrahere. See Subtract. ] (Math.) The sum or number to be subtracted, or taken from another (the minuend) to find the difference. [ 1913 Webster + PJC ]

a. (Anat.) Situated over, or on the dorsal side of, the liver; -- applied to the branches of the hepatic veins. [ 1913 Webster ]

a. [ See Tetrahedron. ] 1. Having, or composed of, four sides. [ 1913 Webster ]

2. (Crystallog.) (a) Having the form of the regular tetrahedron. (b) Pertaining or related to a tetrahedron, or to the system of hemihedral forms to which the tetrahedron belongs. [ 1913 Webster ]

Tetrahedral angle (Geom.), a solid angle bounded or inclosed by four plane angles. [ 1913 Webster ]

adv. In a tetrahedral manner. [ 1913 Webster ]

n. [ So called because the crystals of the species are commonly tetrahedrons. ] (Min.) A sulphide of antimony and copper, with small quantities of other metals. It is a very common ore of copper, and some varieties yield a considerable presentage of silver. Called also gray copper ore, fahlore, and panabase. [ 1913 Webster ]

n. [ Tetra- + Gr. &unr_; seat, base, fr. &unr_; to sit. ] (Geom.) A solid figure inclosed or bounded by four triangles. [ 1913 Webster ]

☞ In crystallography, the regular tetrahedron is regarded as the hemihedral form of the regular octahedron. [ 1913 Webster ]

Regular tetrahedron (Geom.), a solid bounded by four equal equilateral triangles; one of the five regular solids. [ 1913 Webster ]

a. (Crystallog.) Pertaining to a tetrahexahedron. [ 1913 Webster ]

n. [ Tetra- + hexahedron. ] (Crystallog.) A solid in the isometric system, bounded by twenty-four equal triangular faces, four corresponding to each face of the cube. [ 1913 Webster ]