Antonyms of adj glum

2 senses of glum

Sense 1
glum -- (moody and melancholic)

INDIRECT (VIA dejected) -> elated -- (exultantly proud and joyful; in high spirits; "the elated winner"; "felt elated and excited")

Sense 2
dark, dour, glowering, glum, moody, morose, saturnine, sour, sullen -- (showing a brooding ill humor; "a dark scowl"; "the proverbially dour New England Puritan"; "a glum, hopeless shrug"; "he sat in moody silence"; "a morose and unsociable manner"; "a saturnine, almost misanthropic young genius"- Bruce Bliven; "a sour temper"; "a sullen crowd")

INDIRECT (VIA ill-natured) -> good-natured -- (having an easygoing and cheerful disposition; "too good-natured to resent a little criticism"; "the good-natured policeman on our block"; "the sounds of good-natured play")

Similarity of adj glum

2 senses of glum

Sense 1
glum -- (moody and melancholic)
       => dejected (vs. elated) -- (affected or marked by low spirits; "is dejected but trying to look cheerful")

Sense 2
dark, dour, glowering, glum, moody, morose, saturnine, sour, sullen -- (showing a brooding ill humor; "a dark scowl"; "the proverbially dour New England Puritan"; "a glum, hopeless shrug"; "he sat in moody silence"; "a morose and unsociable manner"; "a saturnine, almost misanthropic young genius"- Bruce Bliven; "a sour temper"; "a sullen crowd")
       => ill-natured (vs. good-natured) -- (having an irritable and unpleasant disposition)