<p><strong>Verb</strong></p><ul><li>To move to and fro</li><li>Nautical: to signal by movements of two flags or the like waved according to a code</li></ul><p><strong>Noun</strong></p><ul><li>The act or process of sending messages by the movements of two flags or the like waved according to a code</li><li>A message so signaled</li></ul>