There are several antonyms for the word "co uther," which means to assist or cooperate with someone. The antonyms include hinder, obstruct, impede, oppose, resist, and thwart. These words describe acts of preventing, blocking, or working against someone's efforts, rather than helping them. For instance, one can hinder another person's progress by slowing them down, obstructing their path, or denying them access to necessary resources. Similarly, one can oppose or resist another person's ideas or plans by expressing disagreement, criticism, or opposition. Therefore, the antonyms of co uther highlight the opposite nature of collaboration and cooperation, which are essential for teamwork and achieving shared goals.