Pelvis

n.
  1. (Anat.) The pelvic arch, or the pelvic arch together with the sacrum. See Pelvic arch, under Pelvic, and Sacrum.
  2. (Zoöl.) The calyx of a crinoid.
    3. Pelvis of the kidney (Anat.),
    the basinlike cavity into which the ureter expands as it joins the kidney.