The structural unit of compact bone is called an osteon, or sometimes referred to as a Haversian system. Compact bone is made up of many osteons
<span>The breakdown would be dacryo-cysto-rhino-stomy. Dacryo means a combining form denoting tears. Cysto denotes the sac. Rhino means nose. Stomy means surgical opening. Therefore, this means to surgically restore tears into the nose from the lacrimal sac when the nasolacrimal duct isn’t working.</span>