Chris Columbus -- who was at the helm of the 1993 flick starring Robin as a man disguised as a female nanny -- confirmed to EW that, yes ... there are 3 different versions of 'MD' that exist in the universe, including an R-rated version that got left on the cutting room floor.

Unfortunately for those hungry for an even raunchier cut, there is no NC-17 version -- contrary to what a now-viral tweet suggested earlier this week.

Chris explains the NC-17 quote he once gave in an interview was only made in jest -- but he did say that because of Robin's improv onset and the massive amount of takes they'd do for a given scene ... the team was left with a ton of material, including something just for adults.

He explained it this way ... "[T]here was a deal between Robin and myself, which was, he'll do one or two, three scripted takes. And then he would say, 'Then let me play.'" Chris adds they would go on to do 15 to 22 takes, with new lines and not-so-kid-friendly jokes.

CC doesn't quite recall all the details of Robin's material at the time -- since it's been such a long time since they shot -- but he does say it was funny stuff, in classic Robin fashion.

So the question then becomes ... is he ever planning to release the "true" version? The answer is no -- at least not how overzealous fans want it, anyway. Chris does say he's open to doing a documentary about the making of 'Mrs. Doubtfire,' which he suggested could include some of the R-rated outtakes so folks can watch them for themselves.

But, he's resolute ... the definitive version of 'Doubtfire' is out, and it's the one we all know and love. That's probably a bummer to the Snyder crowd -- but the OG creative has spoken!