Definition of opponens digiti minimi in US English:

opponens digiti minimi

(also opponens minimi digiti)

noun

Anatomy Zoology
  • A muscle of the hand, originating from the hamate bone and flexor retinaculum and inserting into the fifth metacarpal bone, which draws forward and rotates the fifth metacarpal, cupping the palm and assisting in the opposing of the thumb and other fingers.

Origin

Mid 19th century; earliest use found in Todd's Cyclopaedia of Anatomy and Physiology. From scientific Latin opponens digiti minimi from classical Latin oppōnēns + digitī, genitive singular of digitus finger + minimī, masculine genitive singular of minimus smallest.