Tail

A tail is an appendage that is the terminus of a living being's spinal column, usually appearing around the buttocks. In mainstream Smurfs media, Smurfs have short stubby tails that stick out from the back of their pants. Smurfette's tail is mostly unseen, usually covered by her hair or by her clothes, though some may argue whether she actually has a tail at all. It doesn't appear to serve much purpose for a Smurf other than self-identification, but it is considered a weak spot in the comic book story "The Black Smurfs" (and its cartoon show counterpart "The Purple Smurfs"), where a Smurf could be infected with the Black Smurf disease by being bitten either by the black fly or by another Black Smurf.

In the EMPATH: The Luckiest Smurf story series, Empath's tail did serve a purpose in saving Polaris' life, though mostly by accident, when he slipped and fell during a rock-climbing exercise in Psychelia and he grabbed onto the nearest thing that could save him from plummeting. However, it also exposed Empath as being a Smurf and not a Psyche when Polaris realized that the very thing he grabbed also caused his partner pain when he grabbed it.