Let $z \mapsto \overline{z}$ be the D734: Complex conjugation operation.
A D4881: Complex function $f : X \times Y \to \mathbb{C}$ is conjugate symmetric if and only if \begin{equation} \forall \, x \in X : \forall \, y \in Y : f(x, y) = \overline{f(y, x)} \end{equation}