unspring

un- +‎ spring

unspring (third-person singular simple present unsprings, present participle unspringing, simple past unsprang or unsprung, past participle unsprung)

1. (transitive, intransitive) To release or be released by means of a spring.
   • 2010, Elizabeth Mirabel Sain, Gift with Purchase:

     There was a click and the unspringing of a latch.

2. (transitive) To undo the springing of (a mechanism).

   to unspring a trap