#1 gloom n. [somberness, sombreness] a state of partial or total darkness; "he struck a match to dispel the gloom". wn #2 gloom n. [gloominess, somberness, sombreness] a feeling of melancholy apprehension. wn #3 gloom n. [gloominess, glumness] an atmosphere of depression and melancholy; "gloom pervaded the office". wn