Antonyms of verb untie

1 of 2 senses of untie

Sense 1
untie, unbrace, unlace -- (undo the ties of; "They untied the prisoner")
       Antonym of tie (Sense 1)
      => tie, bind -- (fasten or secure with a rope, string, or cord; "They tied their victim to the chair")

Synonyms/Hypernyms (Ordered by Estimated Frequency) of verb untie

2 senses of untie

Sense 1
untie, unbrace, unlace -- (undo the ties of; "They untied the prisoner")
       => undo -- (cancel, annul, or reverse an action or its effect; "I wish I could undo my actions")

Sense 2
untie, undo, loosen -- (cause to become loose; "undo the shoelace"; "untie the knot"; "loosen the necktie")
       => change, alter, modify -- (cause to change; make different; cause a transformation; "The advent of the automobile may have altered the growth pattern of the city"; "The discussion has changed my thinking about the issue")