EX POSTER FACTO: \ECKS Pohsturr Facktoe\ noun: Out of date train and subway signage that advertises long canceled television programs and lost since concluded circuses and Broadway shows. (Deriv. Latin for “Update your damn advertising.”)

Usage: I was gonna take my kid to the Big Apple Circus after seeing an ad for it on Metro-North, but it turned out to be ex poster facto–the show ended last summer.