Antonyms for the phrase "circle back" might include terms like ignore, forget, neglect, disavow, abandon, dismiss, or give up. These words suggest a lack of interest or commitment to returning to an issue or conversation at a later time. Instead of circling back, one might choose to move forward, explore new topics, or simply let go of a particular concern. While circling back can be a useful strategy for resolving conflicts or continuing productive conversations, it is not always the best option. Sometimes it is better to move on and let go of the past.