Webster's gives a rather charming definition of riposte as "a retaliatory verbal sally".
The celebrated star of films such as The King's Speech and TV programmes like Dr. Who, Winston Churchill has many a riposte in his back catalogue.
When George Bernard Shaw invited Churchill to the first night of his play "and bring a friend if you have any", Churchill replied "I can't make the first night, but I will be free for the second if there is one".
Possibly the most famous is Nancy Astor's comment "Winston if you were my husband I would put poison your coffee", Churchill's reply "madam if you were my wife I would drink it".
Another famous riposter was Groucho Marx, not only scripted ones but also as game show host on You Bet Your Life and whenever the occasion called for it.
One that is attributed to Groucho to a woman who had a large amount of children he asked "Why so many?",
"Well I love my husband" was the reply. The riposte was "Well I love my cigar but I take it out of my mouth once in a while".