The beard is what grows on the two jawbones and the chin, and the jaws that we call the "rahat."
This bone here, there is a bone—if one of you opens his mouth—let's begin. This bone here is called the "rahat," this bone. What grows on it is the beard.
What grows on the "lahat," these "rahat" are this bone and the chin.
This is the beard. As for what grows on the cheek, this cheekbone here, and this cheek, that is not part of the beard. Likewise, what grows on the neck, this soft area here.
The neck below the bone, this is not part of the beard.
So the beard is what grows on the "lahat," the two jawbones, these jawbones, and the chin—this is the beard. Therefore, it is permissible to shave what is on the neck, the soft area below.
And also shaving what is on the cheek, on the bone here, and some prohibit removing the hair on the cheek, and some allow it, but leaving it is better.
To avoid disagreement, and knowledge is with Allah, Verheven en Hoog is Hij.