un•bendʌnˈbɛnd(v.)-bent, -bend•ing.

1. (v.t.)to straighten from a bent form or position.

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

3. to release from tension, as a bow.

4. Naut. to loose or untie, as a sail or rope. to unfasten from spars or stays, as sails.

   Category: Nautical

5. (v.i.)to act in an easy, genial manner.

6. to become unbent; straighten.

Origin of unbend:

1200–50

un•bend′a•ble(adj.)