PHP中有$ sign的正式名称吗?

Is there a formal name for $ sign in PHP? I just call it the dollar sign but I have an interview upcoming soon and don't want to sound very immature with the language.

Variables in PHP are represented by a dollar sign followed by the name of the variable.

If they use it, use it, too.

Src: http://www.php.net/manual/en/language.variables.basics.php