Haversian system

Haversian system
(Science: anatomy) The basic unit of structure of compact bone, comprising a haversian canal and its concentrically arranged lamellae, of which there may be 4 to 20, each 3 to 7 microns thick, in a single haversian system.
a haversian canal is a freely anastomosing channel in compact bone containing blood vessels and running longitudinally in the centre of haversian systems of compact osseous Tissue.
It was originally described by Clopton Havers, an english physician, in 1691.

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