[thabaer]

I go for the more specific meaning, like Bill's; the time from moving the pedal to getting force from the engine.

I normally nod my head yes on Magilla's posts, but in this case I wouldn't use RPMs as a direct indication. Even in the case of comparing different flywheel weights when not in gear, I'd call that rev-response instead of throttle. Throttle response to me would be reflected in the immediate torque, that's the first thing you're getting with MFI or carb spitters and it's what you are waiting for while the turbo spools up.

What if you were pulling a 30ft boat ( spank yourself if you've done this with your 911 ) and stepped on it. Would you say your throttle response was bad because the RPMs didn't climb fast or would you say it good because you could feel the engine pulling right away.