Definitions:

1. Latin anatomical term that refers to the opening of the mouth, specifically the space between the lips when they are parted. NOUN
   • The rima oris is bordered by the upper and lower lips.
2. Refers to the entrance to the oral cavity. NOUN
   • In facial reconstruction, restoring the natural shape of the rima oris is essential for function and appearance.

Synonyms:

• mouth
• mouth slit
• oral fissure