IPA: /bəˈlɪdʒ.ə.rən.si/
KK: /bəlˈɪdʒərənsi/
The condition of being involved in a war or conflict, often characterized by aggressive behavior or hostility.
The belligerency of the two nations led to a prolonged conflict that affected many lives.
Belligerency is formed from "bellum" (meaning war) and "-gerent" (from the Latin "gerere", meaning to carry or to conduct). The term describes the state of waging war or being engaged in conflict.
Think of 'bellum' meaning war, and 'gerere' meaning to conduct — belligerency refers to the state of conducting war.