axial vs umbilical

axial

noun
  • A plane parallel to the surface of a tooth. 

  • A flight feather that appears between the primaries and secondaries on some birds. 

adj
  • Belonging to the axis of the body, or to the axis of any appendage or organ 

  • Relating to, resembling, or situated on an axis 

  • In the same direction as the axis, parallel to the axis. 

  • oriented close to the axis running through the centre of a cyclohexane ring, as opposed to equatorial. See w:Axial bond. 

umbilical

noun
  • A cord connecting an astronaut to a spacecraft, or a craft to ground control prior to launch, etc. 

adj
  • Of, or relating to, the navel (umbilicus) or the umbilical cord. 

  • Such that the curvatures of normal sections are all equal to each other. 

How often have the words axial and umbilical occurred in a corpus of books? (source: Google Ngram Viewer )