ˈ(h)yümə(r)lə̇s adjective
1. : lacking in humor
heavy, humorless , slow-moving, methodical — T.H.Fielding
2. : offered, said, or done in dead seriousness : reflecting the lack of a sense of humor
humorless memorizing of 500 dates … for a three-hour third-degree oral examination — L. Ruth Middlebrook
his humorless proposal aroused covert snickers
• hu·mor·less·ness noun -es