任す
まかす · makasu · JLPT N1 · verb-godan
to entrust
🎒 任 = 人 (person) + 壬 (bearing a load): to entrust is to hand a person the load
任 means duty or responsibility, as in 任務 (mission). 任す hands that duty to someone else. The す is okurigana for the verb ending.
任 — person radical 亻 + 壬 (phonetic)
任 combines the person radical 亻 with 壬, which supplies the sound. The original sense centered on a person bearing a load or burden, which extended naturally to 'carrying responsibility,' 'duty,' and 'to appoint someone to a post.' Modern uses like 任务 (task) and 责任 (responsibility) preserve this core idea.