serious genuine grave solemn deep intense sincere heartfelt strong thoughtful earnest major pivotal sullen crucial dinkum dour urgent grim significant sober vital deadpan important pressing sombre formal introspective profound contemplative fundamental key noteworthy ruminative critical essential resolute staid considerable ponderous reflective severe unfunny acute consequential somber stern subdued humourless humorless unhumorous unamusing uncomic lame sad tragic sensible gloomy dull unpleasant depressing pensive dramatic austere glum sedate unhappy depressed pathetic melancholy unsmiling intelligent reasonable boring morose miserable wise unwitty cheerless straight downbeat worrying joyless sobering dismal sorrowful touching dry logical humble standard usual traumatic common normal provocative riveting highbrow mature responsible