expression
can't help but; compelled; irresistible urge
Describes a situation where one is driven by an inner compulsion or unavoidable circumstances, not by rational choice. Often used with verbs like する or なる to express doing something against one's will or better judgment.
やむにやまれず、彼は会社を辞めた。
He couldn't help himself and quit the company.
やむにやまれぬ事情で欠席します。
I will be absent due to unavoidable circumstances.
From the verb 止む (to stop) in a classical negative form, literally 'without being able to stop'. The repetition やむにやまれず intensifies the meaning of being unable to cease or resist.