Cot-1, COT-1, cot-1, or cot−1 may refer to: * Cot-1 DNA, used in comparative genomic hybridization * cot−1y = cot−1(y), sometimes interpreted as arccot(y) or arccotangent of y, the compositional inverse of the trigonometric function cotangent (see below for ambiguity) * cot−1x = cot−1(x), sometimes interpreted as (cot(x))−1 = 1/cot(x) = tan(x) or tangent of x, the multiplicative inverse (or reciprocal) of the trigonometric function cotangent (see above for ambiguity) * cot x−1, sometimes interpreted as cot(x−1) = cot(1/x), the cotangent of the multiplicative inverse (or reciprocal) of x (see below for ambiguity) * cot x−1, sometimes interpreted as (cot(x))−1 = 1/cot(x) = tan(x) or tangent of x, the multiplicative inverse (or reciprocal) of the trigonometric function cotangent (see abo