If you expound an idea or opinion, you give a clear and detailed explanation of it. Schmidt continued to expound his views on economics and politics. = explain Expound on means the same as expound. Lawrence expounded on the military aspects of guerrilla warfare. to explain or talk about something in detail expound on (espondre, from exponere; EXPOSE)
add details, as to an account or idea; clarify the meaning of and discourse in a learned way, usually in writing; "She elaborated on the main ideas in her dissertation"