to straighten from a bent form or position.

to release from the strain of formality, intense effort, etc.; relax

to unbend one's mind.

to release from tension, as a bow.

Nautical .

to loose or untie, as a sail or rope.

to unfasten from spars or stays, as sails.

to relax the strictness of formality or ceremony; act in an easy, genial manner

Imagine him unbending!

to become unbent; straighten.

verb

relax , unwind , condescend , slacken , straighten , vouchsafe