1. （机智的）应答；（尖锐的）反驳
A rejoinder is a reply, especially a quick, witty, or critical one, to a question or remark.

1. (law) a pleading made by a defendant in response to the plaintiff's replication

2. a quick reply to a question or remark (especially a witty or critical one)

e.g. it brought a sharp rejoinder from the teacher

Synonym: retortreturnripostereplicationcomebackcounter