Choanae. For those who don’t know, the pharynx is the tube/cavity that connects your mouth and nose to the esophagus and gets food, spit, mucus, etc. down into the esophagus. It is also the site of post-nasal drip, fun fact.
The choanae are spaces in the body between the nasal cavity and the throat. The definition of that space gets a little term-heavy for those who aren’t in the medical field, so I will leave those out for now.
This space is basically the only way the throat can communicate with the nose and vice versa as far as nerves and things go. So, not only does it allow things to go back and forth between nose and throat, it also allows us to breath without having to open our mouths. Pretty cool, huh?