untie

Short definition from Wiktionary

Verb

1. 1
   To loosen, as something interlaced or knotted; to disengage the parts of.
2. 2
   To free from fastening or from restraint; to let loose; to unbind.
3. 3
   To resolve; to unfold; to clear.
4. 4
   To become untied or loosed.
5. 5
   In the Perl programming language, to undo the process of tying, so that a variable uses default instead of custom functionality.