知らせる
しらせる · shiraseru · JLPT N4 · verb-ichidan
to notify
📢 知る (shiru, to know) + causative せる = make someone know
知らせる is the causative form of 知る (to know): shira- + -seru, literally to cause to know. Causing someone to know something is notifying them. Related noun: お知らせ (oshirase), the word for a notice or announcement.