Cosecant () is a trigonometric ratio. In a right triangle with an angle ,
is the side of the triangle not part of angle , and is the side opposite the right angle.
The reciprocal of cosecant is sine (abbreviated as ), while its inverse is or . Note that cosecant is not being raised to the power of -1; this is an inverse function, not a reciprocal.
The derivative of is , while its antiderivative is .