本丸
ほ
ん
ま
る
Meanings
1
inner citadel; main enclosure
Historical term for the innermost, most fortified part of a Japanese castle. Still used in historical contexts and as a metaphor.
The inner citadel of Himeji Castle is very spacious.
2
Figurative extension of the castle term: the most important part, the heart of a matter, or the main focus. Often used in business, politics, or strategy.
The core of this project is the development of the new product.
The crux of the discussion was the budget issue.
Usage patterns
- 〈場所〉の本丸を攻めるto attack/assault the inner citadel (or figuratively, the heart of an issue)
The enemy army finally attacked the castle's inner citadel.
- 本丸を守るto defend the inner citadel
The soldiers defended the inner citadel to the very end.
- 〈事〉の本丸に迫るto close in on the core of a matter
The investigation finally began closing in on the core of the case.
- 〈事〉が本丸だfor X to be the crux/main target of an issue
In this negotiation, the pricing issue is the real crux of the matter.