DICT.TW Dictionary Taiwan

 Spi·ral n.
 1. Geom. A plane curve, not reentrant, described by a point, called the generatrix, moving along a straight line according to a mathematical law, while the line is revolving about a fixed point called the pole.  Cf. Helix.
 2. Anything which has a spiral form, as a spiral shell.
 Equiangular spiral,a plane curve which cuts all its generatrices at the same angle. Same as Logarithmic spiral, under Logarithmic.
 Spiral of Archimedes, a spiral the law of which is that the generatrix moves uniformly along the revolving line, which also moves uniformly.
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 E·qui·an·gu·lar a.  Having equal angles; as, an equiangular figure; a square is equiangular.
 Equiangular spiral. Math. See under Spiral, n.
 Mutually equiangular, applied to two figures, when every angle of the one has its equal among the angles of the other.
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