gloomy (adj.) Look up gloomy at Dictionary.com
1580s, probably from gloom (n.) even though that word is not attested as early as this one. Shakespeare used it of woods, Marlowe of persons. Gloomy Gus has been used in a general sense of "sullen person" since 1940s, from a comic strip character of that name first recorded 1904. Related: Gloomily; gloominess.