Sigil (computer programming)
In computer programming, a sigil () is a symbol affixed to a variable name, showing the variable's datatype or scope, usually a prefix, as in $foo, where $ is the sigil. Sigil, from the Latin sigillum, meaning a "little sign", means a sign or image supposedly having magical power.
Source: Wikipedia — Sigil (computer programming) (CC BY-SA 4.0)