The state, quality, or condition of lacking humor.(noun)
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Use "humorlessness" in a sentence
""Adapted from William Saroyan's The Laughing Matter, The Banishment's humorlessness is matched only by its bloated self-importance; every take clearly ended with the instruction 'Let's try that again, but with more brooding this time,'" sighs Mike D'Angelo at ScreenGrab over this Competition entry."
"There is a certain humorlessness in your post and others like it that is garden variety insane."
"Fans of overheated melodrama, dorm-room philosophizing, relentless humorlessness, sex-as-rape, and crude science fiction--is that everybody?"