unyielding diligence in one's studies; wearing a hole through one's metal inkstone from constant studying
A yojijukugo (four-character idiom) used to praise or describe extreme perseverance in academic pursuits. The literal image is of grinding through a metal inkstone by constant use.
His passing the exam is truly the fruit of unyielding diligence in his studies.
磨穿鉄硯の精神で研究に打ち込んだ。
He devoted himself to research with the spirit of wearing a hole through his metal inkstone.
Also a yojijukugo about diligent study, but specifically refers to achievements gained through studying by the light of fireflies and snow, emphasizing poverty and hardship.
A common, everyday word for effort or hard work, without the literary or academic nuance of 磨穿鉄硯.
A yojijukugo derived from a classical Chinese story about a scholar who studied so diligently that he wore a hole through his metal inkstone. The exact historical origin is uncertain, but the phrase is conventionally associated with extreme academic perseverance.