What is the action called to cancel or countermand a previous decision?

The correct answer is "Rescind" because this term specifically refers to the action of revoking, canceling, or countermanding a previous decision or motion. In parliamentary procedure, rescinding a motion is a formal way to re-evaluate an earlier decision, allowing the group to take a different course of action if consensus shifts. This is particularly important in decision-making processes, as it allows for flexibility and adaptability to new information or perspectives that may arise after a decision has been made.

Other terms present, such as "Postpone Definitely," refer to delaying a decision to a specific time, while "Commit" involves referring a matter to a committee for further examination. "Obtain the Floor" pertains to the process of gaining the right to speak in a meeting context. These actions, while relevant in parliamentary procedure, do not convey the specific intent of canceling a decision like rescinding does.