noun
biological warfare
Refers to the use of biological agents as weapons in warfare.
生物戦は国際条約で禁止されている。
Biological warfare is prohibited by international treaties.
細菌戦 specifically refers to bacteriological warfare, a subset of biological warfare.
Compound of 生物 (seibutsu, 'organism, living thing') + 戦 (sen, 'war, warfare').