In mathematics, a horn angle, also called a cornicular angle, is a type of curvilinear angle defined as the angle formed between a circle and a straight line tangent to it, or, more generally, the angle formed between two curves at a point where they are tangent to each other.
See also Angle History of geometry Non-Archimedean geometry
References Thomas Little Heath, T.L. (1908). The thirteen books of Euclid's Elements. Vol. 2. The University Press. pp. 39–42.
External links Weisstein, Eric W. "Horn Angle". MathWorld. David E. Joyce, "Definition 8" Euclid's Elements Book I
