part of speech: noun

Sullenness.

part of speech: adjective

Inclined to be alone; ill- humored: as, a sullen disposition; dismal; heavy; gloomy; as, a sullen sky.

part of speech: adverb

Sullenly.

part of speech: adjective

Gloomily angry and silent: malignant: dark: dull.

Gloomily angry; obstinate.

part of speech: adjective

Gloomily angry and silent; cross; sour; in ill humour; mischievous; obstinate; intractable; dark; dull.

part of speech: adjective

Of an unsociable morose disposition; gloomily silent and angry; cloudy; dismal.

Its sullen sound filled me with sadness. "Dreams, Waking Thoughts, and Incidents", William Beckford.

The little army was not sullen now. "The Short Line War", Merwin-Webster.

A flash of sullen rage illumined for a moment the face of the cattle dealer. "A Village of Vagabonds", F. Berkeley Smith.

" The lives of traitors" was the sullen answer. "The Red Rover", James Fenimore Cooper.