This shape takes two names - 'Subroutine' or 'Predefined Process'. Its called a subroutine if you use this object in flowcharting a software program. This allows you to write one subroutine and call it as often as you like from anywhere in the code.
The same object is also called a Predefined Process. This means the flowchart for the predefined process has to be already drawn, and you should reference the flowchart for more information.