expression, ichidan verb
become rampant; be rife
Formal or literary expression used when something undesirable (disease, corruption, etc.) spreads widely and intensely.
感染症が猖獗を極め、多くの人が苦しんだ。
The infectious disease became rampant, and many people suffered.
不正が猖獗
In a society where corruption is rife, trust is lost.