Dorsal interossei muscles of hand
Muscles · Latin: Musculi interossei dorsales manus
In human anatomy, the dorsal interossei (DI) are four muscles in the back of the hand that act to abduct (spread) the index, middle, and ring fingers away from hand's midline (ray of middle finger) and assist in flexion at the metacarpophalangeal joints and extension at the interphalangeal joints of the index, middle and ring fingers.
Definition from Wikipedia, CC BY-SA 4.0.