Bone (noun)

1. The hard, rigid form of connective tissue constituting the skeleton in humans and other vertebrates, consisting primarily of calcium phosphate and collagen.
2. A single piece of a person or animal's skeleton.
3. A thing that is hard and rigid.
4. A thing that is essential or basic.

Origin:

Old english bān, of germanic origin; related to dutch been and german bein.

Examples:

1. The dog buried the bone in the backyard.
2. He broke his leg, fracturing the bone.
3. The bone was too hard to be carved.
4. He picked up a bone and threw it.
5. The bone of contention was the money issue.