The term 'behave dejectedly' can be broken down into five crossword solutions: MOPE (4 letters), SAD (3 letters), DESPONDENT (10 letters), DOWNHEARTED (11 letters), and DEPRESSED (9 letters). This phrase is used to describe someone who is feeling low, disheartened, and generally unhappy. MOPE is a verb meaning to feel or show listlessness or depression, while SAD is an adjective describing a feeling of unhappiness or sorrow. DESPONDENT is an adjective meaning feeling or showing profound hopelessness or discouragement, and DOWNHEARTED is an adjective meaning feeling SAD and dispirited. Finally, DEPRESSED is an adjective meaning feeling very unhappy, hopeless, and helpless. All of these words together describe someone who is behaving in a dejected manner.