Anatomical Snuff Box

A triangular formation of tendons on the posterolateral portion of the hand bounded by the following muscles: Extensor Pollicis Longus, Extensor Pollicis Brevis, and the Abductor Pollicis Longus.

It is called the "Snuff box" because it was often used as a indent on the hand to place snuff (tobacco) for sniffing. The "snuff box" is visible when the thumb is flexed.