9 letters · 17 points in Scrabble
noun a quick reply to a question or remark (especially a witty or critical one)
noun (law) a pleading made by a defendant in response to the plaintiff's replication
originFrom Middle English rejoinder, rejonder, rejoynder, from Middle French rejoindre, with infinitive used as noun frequent in Law French. Doublet of rejoin.
Etymology from Wiktionary, CC BY-SA 3.0