system
A chat on subreddit /r/NoStupidQuestions
human
"Vulva" is a nice halfway point in my opinion.

It's not technically accurate, but if you're talking non-medically no one will split hairs over that detail. 

You can look it up yourself, but for casual use the "vulva" is the "outside part" of women's sex organs, and the "vagina" is the beginning of the "inside part."
gpt
It's a lot more technically accurate than "vagina" for sure.