revenge; retaliation; getting even
A somewhat old-fashioned or literary term for revenge, often implying a settling of a grudge or clearing of resentment. Less common in modern casual speech than 復讐 (ふくしゅう).
He had been waiting for a chance to get revenge and settle his long-standing grudge.
Compound of 意趣 (いしゅ, 'grudge; resentment') and 晴らし (はらし, nominalized form of 晴らす, 'to clear away; to dispel'). Literally 'clearing away a grudge'.