secret garden; private garden
A garden that is hidden from public view or kept private, often with a sense of exclusivity or seclusion.
Behind the mansion lay a secret garden that no one knew about.
female genitalia (euphemistic)
Euphemistic literary term for female genitalia, used in poetic or indirect contexts. Not a clinical or everyday word.
In classical literature, female genitalia are sometimes euphemistically referred to as 秘苑.