adjective, glum·mer, glum·mest.
- sullenly or silently gloomy; dejected.
adjective glummer or glummest
- silent or sullen, as from gloom
1540s, “sullen, frowning,” from Middle English gloumen (v.) “become dark” (c.1300), later gloumben “look gloomy or sullen” (late 14c.); see gloom. Related: Glumly; glumness.