sullen

Definitions:

Gloomily angry and silent; cross; sour; in ill humour; mischievous; obstinate; intractable; dark; dull.
- Nuttall's Standard dictionary of the English language. By Nuttall, P.Austin. Published 1914. (adjective) (adj.) (adjective)
Of an unsociable morose disposition; gloomily silent and angry; cloudy; dismal.
- Etymological and pronouncing dictionary of the English language. By Stormonth, James, Phelp, P. H. Published 1874. (adjective) (adj.) (adjective)
Gloomily angry; obstinate.
- The Clarendon dictionary. By William Hand Browne, Samuel Stehman Haldeman. Published 1894. (adjective) (adj.) (adjective)
Sullenly.
- The Winston Simplified Dictionary. By William Dodge Lewis, Edgar Arthur Singer. Published 1919. (adverb) (adv.) (adverb)
Gloomily angry and silent: malignant: dark: dull.
- The american dictionary of the english language. By Daniel Lyons. Published 1899. (adjective) (adj.) (adjective)
Sullenness.
- Newage Dictionary DB (noun) (n.) (noun)
Inclined to be alone; ill- humored: as, a sullen disposition; dismal; heavy; gloomy; as, a sullen sky.
- The Winston Simplified Dictionary. By William Dodge Lewis, Edgar Arthur Singer. Published 1919. (adjective) (adj.) (adjective)

Usage examples:

It wouldn't help our case to be sullen and it might make it much worse.
- In Her Own Right by John Reed Scott
A sullen cruel man whom no one loves."
- The Coming of the King by James Hocking
Her face became heavy and sullen
- The Trespasser by D.H. Lawrence