剣けんが峰みね

noun

volcanic crater rim; the rim of a volcano

Specifically refers to the sharp, sword-like ridge around a volcanic crater, most famously associated with Mt. Fuji. Often used in the phrase 剣が峰に立つ (to stand on the rim) metaphorically.

• 富ふ士じ山さんの剣けんが峰みねは、登と山ざん者しゃにとって最さい後ごの難なん所しょだ。

  The crater rim of Mt. Fuji is the final challenge for climbers.

noun

sumo ring; wrestling ring

In sumo, the raised ring where matches take place. The term evokes the idea of a critical boundary, similar to the crater rim.

• 力りき士しが剣けんが峰みねに上あがると、観かん客きゃくの拍はく手しゅが湧わき起おこった。

  When the wrestler stepped onto the ring, applause erupted from the audience.

noun

critical situation; sink-or-swim moment; do-or-die position

Metaphorical use derived from the crater rim sense. Describes a high-stakes situation with no room for error, where one wrong move leads to disaster. Common in business, sports, and personal crises.

• 会かい社しゃは資し金きん繰ぐりが厳きびしく、まさに剣けんが峰みねに立たたされている。

  The company is in a dire cash-flow situation, truly standing on the brink.

• 試し合あいは最さい終しゅうセット、剣けんが峰みねの場ば面めんでエースが決きまった。

  In the final set, at the critical moment, an ace was scored.