noun
difficult matter; tough case
Refers to a problem, issue, or case that is hard to handle or resolve. Often used in business, legal, or bureaucratic contexts.
この難件をどう処理するか、まだ決まっていない。
It hasn't been decided yet how to handle this difficult case.
難件が重なって、担当者は大変そうだ。
With tough cases piling up, the person in charge looks overwhelmed.