The quality of being warlike, aggressive, or eager to fight; a combative or hostile temperament.
From Latin 'bellicosus' (warlike, from 'bellum' = war) + '-ity' (suffix forming abstract nouns). Entered English in the 17th century from Latinate philosophical and military writing.
If you study the bellicosity levels of different nations in 1910, you can actually predict which ones would fight in World War I—this single word captures an entire attitude toward conflict!
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