expression, godan verb (-ru)
get irritated; get annoyed; chafe
Describes a state of being inwardly irritated or annoyed, often over small matters. The expression literally means 'to boil one's liver', reflecting the traditional association of the liver with anger.
彼の無責任な態度に肝を煎っている。
I'm getting irritated by his irresponsible attitude.
expression, godan verb (-ru)
Used when someone takes pains to handle a matter or mediate between parties. This sense is less common and may be considered somewhat dated.
彼は両者の間に入って肝を煎ってくれた。
He took the trouble to mediate between the two parties.