A rigid designator is a term that refers to a specific object or individual in all possible worlds. For example, the name Aristotle is a rigid designator because it refers to the same historical figure regardless of the context or scenario being considered. This concept is important in philosophy, particularly in discussions about reference and meaning. In contrast to non-rigid designators, which can refer to different objects in different contexts, rigid designators maintain their reference consistently. For instance, the term "the tallest person" can refer to different individuals in different situations, making it a non-rigid designator. Understanding rigid designators helps clarify how language relates to the objects it describes.