<p><strong>Adjective</strong></p><ul><li>existing only in the imagination or fancy</li><li>not real</li><li>fancied</li><li>an imaginary illness</li><li>the imaginary animals in the stories of Dr. Seuss</li></ul><p><strong>Synonyms</strong></p><ul><li>illusory</li><li>baseless</li><li>chimerical</li><li>shadowy</li><li>visionary</li><li>fanciful</li></ul><p><strong>Antonyms</strong></p><ul><li>real</li></ul><p><strong>Noun</strong></p><ul><li>plural: imaginaries</li><li>Mathematics: imaginary number</li></ul>