Truculent derives from truculentus, a form of the Latin adjective trux, meaning "savage." It has been used in English since the 16th century to describe people or things that are cruel and ferocious, such as tyrannical leaders, and has also come to mean "deadly or destructive" (as in "a truculent disease"). In current use, however, it has lost much of its etymological fierceness. It now frequently serves to describe speech or writing that is notably harsh (as in "truculent criticism") or a person who is notably self-assertive and surly ("a truculent schoolboy"). Some usage commentators have criticized these extended uses because they do not match the savagery of the word's original sense, but they are well-established and perfectly standard.