Glum, morose, sullen, dour, surly all are adjectives describing a gloomy, unsociable attitude. Glum describes a depressed, spiritless condition or manner, usually temporary rather than habitual: a glum shrug of the shoulders; a glum, hopeless look in his eye. Morose, which adds to glum a sense of bitterness, implies a habitual and pervasive gloominess: a sour, morose manner; morose withdrawal from human contact. Sullen usually implies reluctance or refusal to speak accompanied by glowering looks expressing anger or a sense of injury: a sullen manner, silence, look. Dour refers to a stern and forbidding aspect, stony and unresponsive: dour rejection of friendly overtures. Surly implies gruffness of speech and manner, usually accompanied by an air of injury and ill temper: a surly reply.

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