What does supinator mean?
A supinator is primarily the forearm muscle that rotates the hand and forearm so that the palm faces upward or anteriorly. It works in opposition to the pronator, which turns the palm downward. Because the biceps brachii can also contribute to this movement, the supinator muscle is particularly important when the elbow is straight and the forearm is being rotated against resistance. The term can more generally designate a person or device that puts an object into a supine, upward-facing position. Although “supinator” is relatively uncommon outside anatomy, the related verb “supinate” and noun “supination” are familiar in medical and physiological descriptions of movement. The word is also useful in discussions of anatomy, biomechanics, exercise, and the contrasting actions of opposing forearm muscles.
An anatomical muscle that rotates the forearm so that the palm faces upward or anteriorly.
"The supinator is one of the principal muscles responsible for supinating the forearm."
Usually used in anatomical or medical contexts.
A person or mechanism that turns something into a supine or upward-facing position.
"The device acted as a supinator, placing each component in the correct orientation."
The plural is used when referring to multiple anatomical supinator muscles or multiple devices or people that perform the function.
"The forearm supinators are located on the outer side of the upper forearm."
Without the supinator, lifting a palm toward the sky would require a rather different set of muscles.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Where does supinator come from?
The English word comes from Latin supinator, an agent noun derived from supinō, meaning “to turn upward” or “lay on the back,” and supinus, meaning “bent backward” or “lying on the back.” The same Latin root produced English supinate and supination, while supine preserves the related idea of lying with the back downward. Anatomically, the noun became established for the muscle responsible for turning the palm upward.
Related word forms
How supinator is actually used
The word is most common in anatomical and medical contexts. Outside those contexts, it is uncommon and generally refers literally or metaphorically to something that turns something upward.
Easily confused with supinator
A supinator rotates the forearm so the palm faces upward, whereas a pronator turns the palm downward.