Definition:Singular Boolean Function

Definition
A singular boolean function $s : \mathbb B^k \to \mathbb B$ is a boolean function whose fiber of truth is a singleton subset of $\mathbb B^k$.

Also known as
Where the boolean domain $\mathbb B = \set {\T, \F}$ is given a logical interpretation, a singular boolean function is called a singular proposition.

That is, a singular proposition $P$ is one in which there exists one and only one model $\MM \models P$.