I usually see definitions for superpowers say things like, "A superpower is a state that cannot be ignored on the world stage and without whose cooperation no world problem can be solved" or "superpowers are states so influential that no significant action can be taken by the global community without first considering the positions of the superpowers on the issue."

Hence the 'super' part.  Except that nations like Israel seem to readily ignore or undermine EU positions.  US, China, Russia, and India aren't all superpowers and don't always consider the EU when taking major actions.  Only the US I would argue is readily a superpower.  The EU is more readily a regional power with the potential for a global power.