Invoke
It is possible to invoke an object, that means calling a function built with the object as the function name.
Invocation is based on the __invoke magic method.
Being invokable, or invocable, means that an object may be used as a function name.
<?php
class elephpant {
function __invoke($a) {
echo 'I am '.$a;
}
}
$elephpant = new elephpant;
$elephpant('elephpant'); // I am elephpant
?>