I stopped saying it when I grew up, but now I work in an all-female office, and find it funny that it’s used commonly around here; I hear it so much I end up saying it myself (we are a small office - it’s necessary to alert someone if you will be absent & unable to answer the phone).
In our usage, it means “I will be in the restroom (unspoken: to relieve my bowels/bladder).”
Sometimes when it’s just gals within earshot, and the gal is grabbing her purse anyway, she will make some reference to taking care of her monthly business. TMI I say, T.M.I.
My wife and I use this expression quite a lot actually.
It could have something to do with the fact that we have five grandchildren.
To us, it means simply “I’m gonna be in that little room over there”.
If we feel the need to be more specific, usually to indicate expected duration of said tenancy, we might say “I’m gonna go pee” or “I’ve gotta give birth to a Congressman.”
In my mind it’s a general term meaning that one has to visit the necessary.
I think it’s a particularly silly expression, but one that is socially acceptable where many other synonyms that are equally silly and accurate would be confusing, or offensive.
I’ll also hit the head, void, use the necessary, and go to the bathroom. Once the bathroom door closes, it’s no one else’s business but mine what I do in there.
I don’t think I ever actually used the term - my parents (the damn hippies, I guess) taught me and my sister to speak properly fairly early. But when it was used at that age it meant a general “I’m going to go relieve myself in some manner.” Nothing specific about it.
And can I just say I truly am amazed that adults use this phrase with one another? It’s not cute or anything, and really, it’s no more subtle than saying “I need to use the toilet.” All it does, IMO, is make you sound like an idiot, or one of those batty old women who speak to all 30 of their cats as if cute widdle shnookums was an infant.
I once adopted an older dog that had been trained not to defecate until commanded to “go potty.” So I was forced to use this expression, sometimes in public, though I’ve never had children.
All such expressions mean “urinate or defecate.”
In fact, it’s to the point where you can go, “Ew! The cat went to the bathroom on the rug!”
HIJACK: Let’s play identify the quote!
To me, the expression “pee like a racehorse” is always a temptation to ask: “Standing up?”
To me, “going potty” is any use of the bathroom facilities.
Explanation, please?
Given that the “pot” is the toilet bowl, to me the expression “go potty” means to use the toilet bowl.
Well, since the female urethra ( with VERY few exceptions ) is internally located but serves the same purpose as the male penile-centric urethra ( band name !! ), I might suggest these colloquiolisms:
)Cartooniverse
Nah, here it just means “to go mad”. Means the Animaniacs 'toon about “going potty” has added dimensions. 
In the UK it only means " to go crazy"; although the word is used for a baby’s pot, it’s not used as a verb.
:rolleyes: I’m very happy that you were taught to speak properly and never deigned yourself to use harmless little phrases like “go potty” and can now look down upon anyone who has ever used it or (heaven forfend!) continues to use it as a silly little euphemism. I’m also very happy that you can feel assured of your higher intelligence and awesomeness because you can look down upon those idiots who use phrases you never did.