Second-guess is a common phrase that means to doubt or question a decision or action that has already been made. However, there are several other synonyms that could be used in its place, such as doubt, hesitate, question, reconsider, reevaluate, rethink, and hesitate. Each of these words embodies a different shade of meaning and conveys a unique aspect of second-guessing. For instance, questioning implies a need for more information, while reevaluating suggests a desire to reassess and potentially change one's original judgment. Regardless of the synonym used, these words all signify taking a step back and reflecting on a decision before moving forward.