警察
けいさつ · keisatsu · JLPT N4 · noun
police
👮🚓 警察 = warn/guard (警) + inspect (察): those who guard and inspect
警 means to warn or keep watch (as in 警告, warning) and 察 means to examine closely (as in 観察, observation). Sound hook: kei-satsu is close to case-sats, the officers who sit on a case. Add 署 to get 警察署, police station.