Said of a matrix if its inverse exists. That is, a matrix is invertible if there exists another matrix such that BA=, where is the identity matrix.

having an additive or multiplicative inverse

function, (), is invertible if there is a function, (), which is its inverse. In this case, there is only one possible inverse, and we denote it by ). This inverse is characterized by the equations, ()) = and ()) = .

Capable of being inverted or turned inside out.

Capable of being changed or converted; as, invertible sugar.

Incapable of being turned or changed.