This icon is in the shape of a man's face, minus the very top of the head. The eyes are black and filled in and the mouth is curved into a slight frown. On the bottom of the face is a curved line that sections off the chin, appearing like a beard.
This page shows the different variations of the Short Beard from an Icons8 icon pack. Feel free to resize and recolor the icon, and then download the icon in PNG format for free.