Verb
To loosen, as something interlaced or knotted; to disengage the parts of; as, to untie a knot.
To free from fastening or from restraint; to let loose; to unbind.
To become untied or loosed.
Source: Webster's dictionaryundo the shoelace Source: Internet
untie the knot Source: Internet
loosen the necktie Source: Internet
They untied the prisoner Source: Internet
A tightened granny knot can also jam and is often more difficult to untie than the reef knot. Source: Internet
The Devil could not untie it because the Devil is vanquished by the Sign of the Cross. Source: Internet