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