Pel-vim′e-ter.
(Surgical.) An instrument to measure the diameter of the pelvis, principally in the fore-andaft direction. The calipers of Bandelocque have blunt extremities, which are placed respectively on the symphysis pubis and the sacrum, about three inches being deducted for the thickness of the mons veneris, pubis, and the base of the sacrum. Coutouly's instrument is like a shoemaker's foot-measurer, having a sliding lug. It is introduced into the vagina and then separated, so that one projection touches the promontory of the sacrum and the other comes behind the os pubis. The cut represents King's pelvimeter with feelers half opened. It is introduced into the vagina with the piston drawn back. When in position it is pushed gently forward, which makes the feelers in front diverge, the extent of which is indicated on the piston-rod.