English edit

Etymology edit

plane +‎ -al

Adjective edit

planal (not comparable)

  1. Of or relating to a geometric plane.
    • 2009 April 30, Anne Eisenberg, “Solar Tech: Not Just on the Roof Anymore”, in New York Times[1]:
      “Silicon does work well, but it’s always been the limitation that you make silicon devices on hard, rigid, planal surfaces,” Dr. Whitesides said.