noun
Refers specifically to an army division as a military unit. Not used for other meanings of 'division' such as corporate departments or mathematical division.
その師団は前線に配置された。
The division was deployed to the front line.
彼は歩兵師団に所属している。
He belongs to an infantry division.
From 師 (し, 'teacher; military unit') + 団 (だん, 'group; corps'). The kanji 師 historically referred to a military unit of 2,500 men in ancient China, later adapted in Japan for the modern army division.