The term 'quite serious' can be described by four crossword solutions: SOBER (5 letters), SOLEMN (6 letters), EARNEST (7 letters), and SOBERASAJUDGE (13 letters). SOBER is an adjective meaning 'not affected by alcohol, ' while SOLEMN is an adjective meaning 'grave, dignified, and EARNEST.' EARNEST is an adjective meaning 'showing sincere and intense conviction, ' and SOBERASAJUDGE is an idiom meaning 'very serious or strict.' All of these words describe a person or situation that is quite serious.