Arccosecant, denoted as csc⁻¹(x) or arccsc(x), is the inverse function of the cosecant function, which is the reciprocal of the sine function. It is defined for values of x such that x ≤ -1 or x ≥ 1, and its range is typically restricted to the interval [-π/2, 0) ∪ (0, π/2] to maintain it as a function.