<p><strong>noun</strong></p><ul><li>conventional requirements as to social behavior; proprieties of conduct as established in any class or community or for any occasion.</li><li>a prescribed or accepted code of usage in matters of ceremony, as at a court or in official or other formal observances.</li><li>the code of ethical behavior regarding professional practice or action among the members of a profession in their dealings with each other: medical etiquette.</li></ul>