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

I was always under the impression that all a unit had to have to be integrated was an input stage and an amplification (output) stage and thus would include a volume control pot.  But I could be wrong--I often am. 

Oops--I just cross posted with @soix  .  Yes, that's what I always thought.

@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. ?

but what constitutes the "pre-amp"? 

Who cares???  If you have an amp that has a volume control it’s an integrated amp. It matters not if the preamp section is active or passive, it’s still an integrated amp. 

but what constitutes the "pre-amp"?

my guess is the "pre"?