An appendage in the broadest sense's an additional or subsidiary part existing on, or added to, something which can generally still function if the appendage has never existed or's later provided or grown, or will still perform a primary function if the appendage's removed. Biological context An Appendage's an external body part, or natural prolongation, that protrudes from an organism's body, such as a vertebrate's limbs. In invertebrate biology, "appendage"'s a general term that covers any… (More on Appendages)