Levator labii superioris
Muscles
The levator labii superioris (pl. levatores labii superioris, also called quadratus labii superioris, pl. quadrati labii superioris) is a muscle of the human body used in facial expression.
It is a broad sheet, the origin of which extends from the side of the nose to the zygomatic bone.
Definition from Wikipedia, CC BY-SA 4.0.