In physics and Math, it was always understood that rates where a rate of change, typically per time such as speed and acceleration and such. But now I am confused. Different dictionary define rates as any measure, quantity, or frequency, typically one measured against some other quantity or measure. They give examples like $/pound, flowers/person, miles/gallon, miles/ hour So back to an earlier post, would that make pressure a rate? I know it is not a rate as in speed or anything like that. But I am curious I have never thought of it before and would like to know how others define pressure? In the end, I don't want to get more confused, I just want to simply know what a rate is and if this definition is true, should I somehow be defining pressure as rate?