The term 'quite mad' can be described by three crossword solutions: POSSESSED (9 letters), LOCO (4 letters) and IRATE (5 letters). POSSESSED means to be controlled by a supernatural force, while LOCO is a slang term for crazy or insane. IRATE is an adjective meaning to be extremely angry. Therefore, the term 'quite mad' can be interpreted as being under the influence of a supernatural force, being crazy or insane, or being extremely angry.