The Vet is a location that only appears in the episode "Pineapple Invasion." It is short for "Veterinarian" where people take their sick pets to.
The exterior of the Vet is a metallic red in color. The sign that says "Vet" is over the door and is gray/silver in color. It also has a single window.
SpongeBob takes Gary to the Vet to get his shell inspected. When Purple Doctorfish opens up Gary's shell, he discovers Plankton inside holding onto a piece of paper. It is revealed that Plankton has been hallucinating due to breathing in too much of Gary's fumes and believes he has got the Krabby Patty Secret Formula (which actually turns out to be one of SpongeBob's old grocery lists). Plankton then runs off from the Vet thinking he has won.