本部
ほんぶ · honbu · JLPT N2 · noun
headquarters
🏢 本 (main/origin) + 部 (department) = the main department, i.e. headquarters
本 means origin or main, and 部 means department or section. Together they name the main department that the other branches report to.
本 — tree 木 + mark at base
本 is a pictograph of a tree (木) with a stroke at its base, marking the roots. From this 'root' meaning it extended to 'origin,' 'source,' and 'foundation.' In modern usage it also serves as a measure word for bound objects like books.
部 — 阝(邑) right + 咅 phonetic
The right-side 阝 derives from 邑 (city/settlement), giving the meaning of a region, district, or administrative division. The left side 咅 supplies the sound. Originally referring to a settlement, the meaning broadened to 'part,' 'section,' or 'ministry.'