Definition:Singular Boolean Function

A singular boolean function $$s : \mathbb{B}^k \to \mathbb{B}$$ is a boolean function whose fiber of truth is a single element of $$\mathbb{B}^k$$.

Where the boolean domain $$\mathbb{B} = \left\{{T, F}\right\}$$ 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 only one model $$\mathcal{M} \models P$$.