"L'esprit de l'escalier (or l'esprit d'escalier), usually translated as “staircase wit”,..."

“L'esprit de l'escalier (or l'esprit d'escalier), usually translated as “staircase wit”, is the act of thinking of a response, argument or clever comeback when it is too late to deliver it.”

- L'esprit de l'escalier - Wikipedia, the free encyclopedia