Bone

In animal anatomy, bone is a word used to describe the rigid organs that make up our endoskeleton. It is generally fairly hard, but there are certain bones that are more fragile and brittle than others. Sometimes, as a person ages, their bones become more brittle and easier to break. Once, and elderly man was skiing and he slipped and broke the bone in his leg.

Appearances/References
Super Friends
 * Season 1: The Weather Maker