<p><strong>Interjection</strong></p><ul><li>(used as an expression of surprise, pain, disapproval, etc.): <em>Oh, just look at how pretty it is now that you've finished painting! Oh, no! I misplaced my keys again.</em></li><li>(used in direct address to attract the attention of the person spoken to): <em>Oh, John, will you take these books?</em></li></ul><p><strong>Noun</strong></p><ul><li>plural: oh's, ohs.</li><li>the exclamation “oh.”: <em>She gave a little oh of surprise when she discovered her shoes had disappeared.</em></li></ul><p><strong>Verb</strong></p><ul><li>(used without object) to utter or exclaim “oh.”: <em>The hammer dented the wood trim and he ohed in dismay.</em></li></ul>