\begin{definition}[Definition:Constant Symbol]
Let $\LL$ be a formal language (for example, the language of predicate logic $\LL_1$).
A '''constant symbol''' is a letter of $\LL$ used to describe a constant.
The name '''constant symbol''' is a gesture to the reader to make clear what such a symbol should (intuitively) represent in the formal language $\LL$.
\end{definition}