- relax (v.)
- early 15c., "to make (something) less compact or dense," from Old French relaxer (14c.), from Latin relaxare "relax, loosen, open," from re- "back" (see re-) + laxare "loosen," from laxus "loose" (see lax). Of persons, attested from 1837, "to become less formal;" meaning "to become less tense" is recorded from 1935. Related: Relaxed; relaxing.