"Caudal appendages" refer to the tail-like structures found in some animals. The antonyms for this term would include "head appendages" or "anterior appendages," referring to appendages found on the front of the animal rather than the back. However, in many animals, including humans, there are no distinct appendages on either end of the body. Instead, we have limbs that can be used for various purposes, such as running or grasping objects. Some animals have appendages on all parts of their body, such as crabs with claws on their legs and pinchers at the front of their body. Ultimately, the antonyms for "caudal appendages" depend on the specific creature being referred to and its unique body structures.