noun
major war; great war; world war
Refers to a large-scale war, often used for world wars or conflicts of global significance. Can be used in historical or speculative contexts.
第一次世界大戦は、当時「大戦争」と呼ばれた。
World War I was called the 'Great War' at the time.
もし第三次大戦争が起これば、人類は滅びるだろう。
If a third world war breaks out, humanity will probably perish.
世界大戦 is the standard term for 'world war' (e.g., 第一次世界大戦). 大戦争 is a less formal, more dramatic synonym.
Compound of 大 (dai, 'big, great') + 戦争 (sensō, 'war'). A straightforward Sino-Japanese formation.