Truculent means aggressively defiant and ready to argue. Arms folded, chin out, and looking for a fight.
It describes manner rather than action, so a truculent teenager or a truculent response is challenging without necessarily doing anything. The word is formal and slightly literary. Its Latin root means fierce or savage, which is a good deal stronger than the modern sense. Belligerent is the close neighbour and is more openly aggressive, while sullen is silent where truculent answers back.
1adjectivetruculentDefiant and aggressively ready to argue.
“He was truculent with every official he met.”
Truculent has softened. Latin trux meant fierce or wild and truculentus meant savage, so the word has come down from cruelty to mere belligerence.
Proto-Indo-European
*twerḱ-
Latin
truculentus — fierce, savage
English, today
truculent
Built from
First attested circa 1540, from Middle French -, from Latin truculentus (“fierce, savage”), from trux (“fierce, wild”).
Etymology from Wiktionary, CC BY-SA