Being moody, annoyed, or bad-tempered, and showing it by being quiet and withdrawn rather than saying what's wrong. A sulky person seems to be pouting or refusing to engage with others.
Possibly derived from 'sulks,' which has obscure origins but may relate to Old Norse or Scandinavian words meaning 'to sit alone.' The adjective form emerged in English around the 1700s to describe someone with a brooding, withdrawn temperament. The exact origin is debated among etymologists but suggests a person sitting apart from others in silence.
We also use 'sulky' as a noun for a light, two-wheeled horse-drawn cart—and there's a fascinating connection: both meanings capture the idea of withdrawal and isolation, whether it's a person brooding alone or a slim vehicle that seems almost to retreat into minimalism!
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