Is there a clear definition of what "Integrated" means?

@soix but what constitutes the "pre-amp"? Any kind of driver or input stage that increases the signal before the output amplification? And a variable resistor which modulates the grid of the input stage ie volume control pot. ?

@whart Well this touches on why I am asking. If I look up most tube amp designs, PP, SE, and a variety of power tubes, the designs usually include the input stage: There is some twin triode doing some initial amplification usually, and discussions of coupling capacitors or transformer coupled etc. This includes guitar amps, too.

So, are these all tube integrated amps? Because nobody really calls them that, just "tube amps". But it kind of makes sense, if so.