expression, i-adjective
unable to back out; can't withdraw; can't stop now
Used when one is in a situation where retreating, stopping, or compromising is no longer possible, often due to pride, momentum, or obligation.
ここまで来たら、後に引けない。
Having come this far, I can't back out now.
彼は一度言い出したら後に引けない性格だ。
He's the type who, once he says something, can't back down.
Kana spelling of the first part; less common but still used.
From 後 (あと, 'after' or 'later') + に + 引けない (negative potential of 引く, 'to pull back'). Literally 'cannot pull back afterward'.