noun
back-alley doctor; unlicensed doctor; quack
Refers to a doctor practicing without a proper license, often in an illegal or underground setting. Carries a negative, shady connotation.
彼は闇医者に手術を受けて、ひどい目にあった。
He had a terrible experience after undergoing surgery by a back-alley doctor.
その地域では闇医者がまだ活動しているらしい。
It seems unlicensed doctors are still operating in that area.
Compound of 闇 (yami, 'darkness; illegal') and 医者 (isha, 'doctor'). The exact historical origin is uncertain, but the term likely arose to describe doctors operating outside the law, hidden from authorities.