When you take a shit and either forgetfully or purposefully don't flush the toilet, and the next person to use the bathroom finds your crap left in the bowl.

Also, when you do flush the bowl but a persistently buoyant turd doesn't go down with the water and floats back up, again to be found by the next person to use the toilet.

Anatidaephobia is defined as a pervasive, irrational fear that one is being watched by a duck. The anatidaephobic individual fears that no matter where they are or what they are doing, a duck watches.

Anatidaephobia is derived from the Greek word "anatidae", meaning ducks, geese or swans and "phobos" meaning fear.