A rhetorical device is a technique used by writers or speakers to persuade, inform, or entertain their audience. It involves using language in a creative and effective way to convey a message or create an emotional response. Rhetorical devices include techniques such as metaphors, similes, analogies, personification, hyperbole, irony, and many others. These tools help writers and speakers to make their points more vividly, memorably, and persuasively.