To return a wave to someone you think is waving at you, but is actually waving to the person behind you. Usually results in embarrassment and introversion.

Adj. Something that is expected to have a long lifespan by virtue of having existed for a long time, based on the lindy effect, named for the New York restaurant Lindy's, coined by Albert Goldman and popularized by Nassim Taleb.

To wave to somebody you thought was someone you knew but really you just waved to a complete stranger. That complete stranger gives you a look of dismay not for the wave but for the enthusiasm and excitement you conveyed along with your wave.