<p><strong>Noun:</strong></p><ul><li>The act of interjecting.</li><li>Something interjected, as a remark.</li><li>The utterance of a word or phrase expressive of emotion; the uttering of an exclamation.</li><li>Grammar: Any member of a class of words expressing emotion, distinguished in most languages by their use in grammatical isolation, as "Hey!" "Oh!" "Ouch!" "Ugh!"</li><li>Any other word or expression so used, as "Good grief!" "Indeed!"</li></ul>