つめのあかをせんじてのむ

爪 の 垢 を 煎 じて 飲 む

  1. expressions (phrases, clauses, etc.), Godan verb with 'mu' ending

    to take a lesson from (someone serving as an example), to learn from someone's example, to boil the dirt under (someone's) fingernails and drink it
    idiomatic expression