Feel free to use your own favorite definitions for words and call Brad Pitt whatever you want... he still spent a ton of time in the gym doing weight exercises, just like a bodybuilder does.
I think usually body builders are associated with insane size which mostly people don't think can be achieved naturally.
But I've had girls tell me that Arnold during his peak in bodybuilding was all natural and that he has superior genetics than everyone else on the planet which helped them achieve that size.
Just like every moderately serious athlete does.
The word you're looking for is athletic.