innie

noun5

1. •
   (informal) Anything concave.
2. •
   (informal, slang) A navel that is formed of a hollow in the abdomen (as opposed to one that protrudes from the abdomen).
3. •
   (informal, slang) A vulva with inner labia minora.
4. •
   (informal, euphemistic) A vulva seen as an inverted version of a penis.
5. •
   An introvert.