<p><strong>Noun</strong></p><ul><li>the act of congratulating.</li><li>congratulations, an expression of joy in the success or good fortune of another.</li></ul><p><strong>Interjection</strong></p><ul><li>congratulations, (used to express joy in the success or good fortune of another): Congratulations! You have just won the lottery!</li></ul><p><strong>End of Response</strong></p>