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Medical Definition of Costal process
1. An apophysis extending laterally from the transverse process of a lumbar vertebra; it is the homologue of the rib. Synonym: processus costalis. (05 Mar 2000)
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1. An apophysis extending laterally from the transverse process of a lumbar vertebra; it is the homologue of the rib. Synonym: processus costalis. (05 Mar 2000)