What is a vagina?

The vagina (from Latin, literally "sheath" or "scabbard") is a fibromuscular tubular tract leading from the uterus to the exterior of the body in female placental mammals and marsupials, or to the cloaca in female birds, monotremes, and some reptiles. Female insects and other invertebrates also have a vagina, which is the terminal part of the oviduct. The Latinate plural (rarely used in English) is vaginae.
In common speech, the term "vagina" is often used to refer to the vulva or female genitals generally; strictly speaking, the vagina is a specific internal structure and the vulva is the exterior genitalia only.

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There are several uses of the word pussie or pussy;
A crude name for a girls vagina.
An affectionate name for a cat.
An insulting term for someone who is considered to lack courage.