relax

Concise Oxford English Dictionary © 2008 Oxford University Press:
relax/rɪˈlaks/

▶verb

• 1 make or become less tense or anxious.

  ■ cause (a limb or muscle) to become less rigid.

• 2 rest from work or engage in a recreational activity.

• 3 make (a rule or restriction) less strict.

• 4 straighten or partially uncurl (hair) using a chemical product.

– derivatives
relaxed adjective,
relaxedly adverb,
relaxedness noun,
relaxer noun.

– origin ME: from L. relaxare, from re- (expressing intensive force) + laxus ‘lax, loose’.