The endoskeleton of a horse.
The definition of an endoskeleton is the internal bone or cartilage structure of animals which have a vertebra and some animals without vertebra.
An example of an endoskeleton is the skeleton inside a human body.
the internal bony, cartilaginous, or chitinous supporting structure in vertebrates, echinoderms, etc.
An internal supporting skeleton, derived from the mesoderm, that is characteristic of vertebrates and certain invertebrates.
From endo- + skeleton.