1. A unit of pressure equal to 1 megadyne (10
2. A metal segment of greater length than width that serves to connect two or more parts of a removable partial denture.
3. A segment of tissue or bone that unites two or more similar structures.
4. In veterinary medicine, the ridged structure on the sole of the horse hoof that connects the wall of the hoof with the sole adjacent to the frog, one bar to each side of the frog. It forms the lateral wall of the paracuneal groove (lateral sulcus) of the frog at the heel.
The definition information for bar is provided by Stedman's. You can search our medical dictionary here.