• WordNet 3.6
    • n endoskeleton the internal skeleton; bony and cartilaginous structure (especially of vertebrates)
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Webster's Revised Unabridged Dictionary
    • n Endoskeleton (Anat) The bony, cartilaginous, or other internal framework of an animal, as distinguished from the exoskeleton.
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Century Dictionary and Cyclopedia
    • n endoskeleton In anatomy, the internal skeleton or framework of the body; the whole bony, chitinous, cartilaginous, or other hard structure which lies within the integument, and is covered by flesh and skin, as distinguished from the exoskeleton. In man and nearly all other mammals it constitutes the whole skeleton. In invertebrates the term covers any hard interior framework supporting soft parts, as the apodemal system of arthropods, the cuttle of a squid, etc. The endoskeleton of vertebrates is divisible into two independent portions: the axial endoskeleton, belonging to the head and trunk, and the appendicular endoskeleton, to the limbs. The axial endoskeleton consists of the entire series of vertebral and cranial segments, including ribs, breast-bones, hyoid bones, and jaws. The appendicular endoskeleton consists of the bones of the limbs, regarded as diverging appendages, and inclusive of the pectoral and pelvic arches (shoulder-and hip-girdles), by which these appendages are attached to the axial elements.
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Chambers's Twentieth Century Dictionary
    • n Endoskeleton en-dō-skel′e-ton the internal skeleton or framework of the body
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Webster's Revised Unabridged Dictionary
Endo-, + skeleton,


In literature:

Endoskeletal: relating or referring to the endoskeleton.
"Explanation of Terms Used in Entomology" by John. B. Smith
Apparently have endoskeleton, but organization of the internal organs remains obscure.
"The Native Soil" by Alan Edward Nourse
The alien had an endoskeleton, but he also had a tough hide that was somewhat like thick, leathery chitin.
"Anything You Can Do ..." by Gordon Randall Garrett
The skeleton of the Mammalia consists almost solely of the endoskeleton.
"The Cambridge Natural History, Vol X., Mammalia" by Frank Evers Beddard