I think most of the time AD&D is referred to as First Edition. https://en.wikipedia.org/wiki/Editions_of_Dungeons_%26_Dragons https://en.wikipedia.org/wiki/Edi

I think most of the time AD&D is referred to as First Edition. https://en.wikipedia.org/wiki/Editions_of_Dungeons_%26_Dragons https://en.wikipedia.org/wiki/Editions_of_Dungeons_%26_Drago... But to extend on your point - maybe Original D&D is like Forth in this analogy?