警官
けいかん · keikan · JLPT N5 · noun
policeman
👮 警官 = warn/guard (警) + official (官): the guarding official
警 means to warn or guard, as in 警察 (keisatsu, police). 官 is a government official. Kei-kan is the official who guards, a slightly formal word for a police officer.
官 — roof 宀 + mound/many 㠯
Originally a pictograph showing a building (roof 宀) over stacked mounds or seats (㠯), depicting an official residence or government office. The meaning extended from the building itself to the officials who worked there, and then broadly to 'official' or 'government.'