#aftertort

Some friends and I were talking about words in certain languages which have no direct translation into another language. One that came up was the German Treppenwitz (lit. 'staircase joke', cf. French l'esprit de l'escalier). We probably all know the feeling of thinking of the perfect retort when it's too late, that perfect retort being the Treppenwitz. 

Anyway, I felt my English deserved a word for this as well, and for that reason I invented aftertort. It's made up of after + tort (cf. re-tort) and also serves as a play on afterthought (it works better if you speak a non-rhotic English variety).