supination

[soo-puh-ney-shuh n]

noun

rotation of the hand or forearm so that the palmar surface is facing upward (opposed to pronation).
a comparable motion of the foot, consisting of adduction followed by inversion.
the position assumed as the result of this rotation.

Origin of supination

First recorded in 1660–70; supinate + -ion

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

The radius and ulna are parallel in the most natural position of supination.
Gunshot Roentgenograms
Clyde S. Ford
Thus, the bear (plantigrade) has five digits, and the power of performing the movements of supination and pronation.
Artistic Anatomy of Animals
douard Cuyer
Should we, then, in order to maintain the symmetry with human anatomy, first study the forearm in the position of supination?
Artistic Anatomy of Animals
douard Cuyer
The forearm lies in supination, with its posterior surface next to the plate.
Gunshot Roentgenograms
Clyde S. Ford
The movements allowed at these three articulations are called pronation and supination of the radius.
Encyclopaedia Britannica, 11th Edition, Volume 15, Slice 5
Various

1660s, from Latin supinationem (nominative supinatio), noun of action from supinare (see supine).