painstaking; excruciating; grueling
Idiomatic expression describing effort or hard work so intense it feels as if blood is oozing out. Often used with nouns like 努力 (effort) or 練習 (practice).
彼の血のにじむような努力が実を結んだ。
His painstaking efforts bore fruit.
血のにじむような練習を経て、彼女は優勝した。
After grueling practice, she won the championship.
Standard kanji-kana mixed spelling for this idiomatic expression.
Uses the kanji 滲 for 'ooze/seep', which is less common but still seen.
Literally 'as if blood oozes', a figurative expression likening extreme effort to the sensation of bleeding. The exact origin is uncertain, but it is a natural metaphor in Japanese for intense, painful exertion.