関(せき)ヶ原(はら)

せきがはら
noun (proper)
Sekigahara; a decisive showdown
historyproper-nounplace-name
1. Sekigahara (battlefield in Gifu Prefecture); the 1600 battle fought there
A basin in western Gifu Prefecture where Tokugawa Ieyasu's eastern army defeated the western coalition in 1600, opening the way to the Edo shogunate.
関ヶ原(せきがはら)は岐阜県(ぎふけん)にある。
Sekigahara is in Gifu Prefecture.
関ヶ原(せきがはら)の戦(たたか)いは1600年(ねん)に起(お)きた。
The Battle of Sekigahara took place in 1600.
After the Battle of Sekigahara, Tokugawa Ieyasu brought the country's feudal lords under his control.
2. decisive showdown; make-or-break moment
By extension, any contest that will settle everything — a final match, a crucial negotiation, a career-defining exam.
明日(あした)の試合(しあい)が関ヶ原(せきがはら)だ。
Tomorrow's match is our Sekigahara.
These negotiations will be the decisive showdown.
For students taking entrance exams, that one week in February is said to be their Sekigahara.

Common expressions

Cultural note

The battle is the best-known single day in Japanese history, retold constantly in novels, films, and taiga dramas. Because everyone knows how much rode on it, the name works in ordinary conversation as shorthand for a decisive moment, much as "Waterloo" does in English — though Sekigahara names the contest itself rather than a defeat.