1580s, "action of distorting," from Latin distortionem (nominative distortio), noun of action from past participle stem of distorquere (see distort). Figurative use (of words, etc.) from 1640s.
distortion dis·tor·tion (dĭ-stôr'shən)n.
A twisting out of normal shape or form.
A psychological defense mechanism that helps to repress or disguise unacceptable thoughts.