The term "csc" refers to the cosecant function in trigonometry, which is the reciprocal of the sine function. In a right triangle, the cosecant of an angle is defined as the ratio of the length of the hypotenuse to the length of the opposite side. It is commonly used in various mathematical applications, including calculus and physics. In mathematical notation, the cosecant of an angle θ is expressed as csc(θ) = 1/sin(θ). The cosecant function is undefined for angles where the sine is zero, such as 0° and 180°. Understanding csc is essential for solving problems involving triangles and periodic functions.