Wiktionary
vb. (context transitive English) To free from constraints.
Usage examples of "unconstrain".
To these observations, although they seemed to come from a heart occupied by more gloomy as well as more important cares, Isabella endeavoured to answer in a manner as free and unconstrained as it was possible for her to assume, amid the involuntary apprehensions which crowded upon her imagination.
She was perfectly unconstrained and unaffected: as modestly silent about her productions, as she was generous with their pecuniary results.
He laughed -- his unexpected, unconstrained, exuberantly wanton laugh.
Thereafter, both spoke of Egremont, when at all, in an unconstrained way.
The Dales may have been well-bred and lived in a large house, but they also had a stubborn gene which cropped up from time to time, a restless, inventive, unconstrained gene as capable of causing great mischief as of creating great beauty.