Did you even read the definition you provided here?
a : to decrease the flow of (as steam or fuel to an engine) by a valve
b : to regulate and especially to reduce the speed of (as an engine) by such means
c : to vary the thrust of (a rocket engine) during flight
Without a throttle ALL engines would run at FULL speed/RPM. There would be no restriction to the amount of fuel entering the engine which means your car (for example) would run at maximum RPM at all times. Now newer engines use fuel injectors, but those do not have a "throttle". Instead the injectors are turned off and off releasing fuel.
Don't give me the bull about how you meant a "rocket car", because that's baloney. What you found is the only way to even sorta prove you could on the fringe be right. The meaning of throttle is to restrict. A throttle is naturally in the off position almost completely restricting the flow of fuel. You have to force it out of its natural state in order to allow for an engine to increase in rpm. This is the normal and accepted definition. Some obscure definition for rocket engines it is not.
Again Turbo boost is the complete opposite of Throttle. I would recommend you take combustion engines 101 before you argue with me again on this. I'm going to assume you have never worked on a combustion engine of any type since you clearly do not understand the definition of Throttle.
a.You are getting a little to bent out of shape over this.Everyone knows what he meant.
B.You are wrong.