The definition of glum is being or looking gloomy or sad.
(adjective)An example of glum used as an adjective is in the phrase "a glum expression," which means a sad expression.
See glum in Webster's New World College Dictionary
See glum in American Heritage Dictionary 4
adjective glum·mer, glum·mest
Origin:
Origin: Probably akin to Middle English gloumen, to become dark; see gloom
.Related Forms:
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