一いちか八ばちか

expression, noun which may take the genitive case particle 'no'

sink or swim; all or nothing; hit or miss; make or break

Describes a risky situation where the outcome is either complete success or total failure, with no middle ground. Often used adverbially with で or as a の-adjective.

• 一いちか八ばちか、その計けい画かくに全ぜん財ざい産さんを賭かけてみた。

  I took a sink-or-swim gamble and bet all my money on that plan.

• 一いちか八ばちかの勝しょう負ぶに出でるしかなかった。

  I had no choice but to go for an all-or-nothing contest.