backbone vs volume

backbone and volume both are nouns.

Word	Noun	Adjective	Verb	Adverb
backbone	Yes	No	No	No
volume	Yes	No	No	No

backbone (noun)	volume (noun)
the part of a network that connects other networks together	physical objects consisting of a number of pages bound together
the part of a book's cover that encloses the inner side of the book's pages and that faces outward when the book is shelved	the magnitude of sound (usually in a specified direction)
fortitude and determination	the property of something that is great in magnitude
the series of vertebrae forming the axis of the skeleton and protecting the spinal cord	a publication that is one of a set of several similar publications
a central cohesive source of support and stability	the amount of 3-dimensional space occupied by an object
	a relative amount