Dictionary.net

• When the shaft of a long bone has been broken through, and the extremities have been brought in exact juxtaposition, the now matter, first ossified, is that which occupies the central portion of the deposit, and thus connects the medullary cavities of the broken ends, forming a kind of plug, which enters each. This was termed by M. Dupuytren the provisional Callus.

1846 - Medical lexicon: a dictionary of medical science
By Robley Dunglison