origin; source; main branch of a family
Refers to the original source or root of something, or the main lineage in a family context. The family sense is less common in modern everyday speech.
この問題の本元を探る必要がある。
We need to investigate the origin of this problem.
He inherits the main branch of the family.
original home; birthplace; originator
Compound of 本 (hon, 'main, true') and 元 (moto, 'origin, source'). The exact historical derivation is uncertain, but the combination naturally yields the meaning 'true origin' or 'main source'.