What Does It Mean When Cats Tail Shakes. If your cat’s tail is twitching or vibrating, you should identify the cause of the movement. When your cat’s tail is moving so fast it seems to be vibrating, it means your cat is annoyed or nervous about something.
This is often a greeting sign when they see someone they know and like. In other words, if you are petting your cat and they start thrashing their tail, they are trying to tell you to stop. If it’s being caused by anxiety or fear, you can remove the cause of this anxiety, which will stop the tail twitching, although it can take some time before your cat is completely calm.