hyperegolic

a. (Rocketry) Igniting spontaneously when mixed together; -- used of pairs of substances which react violently with evolution of heat when mixed, as for example hydrazine and nitrogen tetroxide. Such combinations of substances are convenient for use in liquid-fueled rockets, as they do not require a source of ignition. [ PJC ]

{ } a. [ L. hyperbolicus, Gr. "yperboliko`s: cf. F. hyperbolique.] 1. (Math.) Belonging to the hyperbola; having the nature of the hyperbola. [1913 Webster]

2. (Rhet.) Relating to, containing, or of the nature of, hyperbole; exaggerating or diminishing beyond the fact; exceeding the truth; as, an hyperbolical expression. “This hyperbolical epitaph.” Fuller. [1913 Webster]

Hyperbolic functions (Math.), certain functions which have relations to the hyperbola corresponding to those which sines, cosines, tangents, etc., have to the circle; and hence, called hyperbolic sines, hyperbolic cosines, etc. --
Hyperbolic logarithm. See Logarithm. --
Hyperbolic spiral (Math.), a spiral curve, the law of which is, that the distance from the pole to the generating point varies inversely as the angle swept over by the radius vector. [1913 Webster]