octant
 oxford
 views  updated May 14 2018octant eighth part of a circle; (spec. astron.) point 45° (i.e. ⅛ of 360°) distant from another. XVII. — L. 
octāns, 
-ant- half quadrant, f. 
octō EIGHT.
  The Concise Oxford Dictionary of English Etymology T. F. HOAD
   octant
 oxford
 views  updated Jun 27 2018 A Dictionary of Computing JOHN DAINTITH