Philtrum

There's a sweet smart kid in the neighborhood that has such a huge space between his upper lip and his button nose that he looks like he stepped out of the Dr. Seuss book The Cat in the Hat. He is adorable! I finally had to find the name for this space on the face.

Philtrum
Definition:
philtrum : the vertical groove on the median line of the upper lip
Origin:
In Greek, the primary meaning of philtrum is "love potion" – which suggests that seductive powers were attributed to this facial feature.
- Merriam Webster Dictionary