<p><strong>Noun</strong></p><ul><li>Greek History: Any of a class of professional teachers in ancient Greece who gave instruction in various fields, such as general culture, rhetoric, politics, or disputation.</li><li>A person belonging to this class at a later period who, while professing to teach skill in reasoning, concerned himself with ingenuity and specious effectiveness rather than soundness of argument.</li><li>A person who reasons adroitly and speciously rather than soundly.</li><li>A philosopher.</li></ul><p><strong>End of Response</strong></p>