Adjective: twisted into an unnatural or unusual shape; Verb: past tense of contort (to twist or bend out of shape).
From Latin contortus, past participle of contorquere (to twist together), from con- + torquere (to twist). The idea of twisting something along with force.
Medieval torture specialists had whole arsenals of devices called 'engines of contortion'—contort comes straight from that violence, which is why the word carries such a visceral sense of wrongness, even when describing a yoga pose or a facial expression.
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