UNKNOT
unravel, unknot, unscramble, untangle, unpick
(verb) become or cause to become undone by separating the fibers or threads of; “unravel the thread”
Source: WordNet® 3.1
Etymology
Noun
unknot (plural unknots)
(mathematics) In knot theory, a loop that is not knotted.
Verb
unknot (third-person singular simple present unknots, present participle unknotting, simple past and past participle unknotted)
(transitive) To unfasten (a knot).
Source: Wiktionary
Un*knot", v. t. Etym: [1st un- + knot.]
Definition: To free from knots; to untie.
Source: Webster’s Unabridged Dictionary 1913 Edition