indirect vs perpendicular

indirect

adj
  • Not focused straight at the target or subject, but by more subtle means 

  • Not of obvious or immediate cause, but as a secondary result 

  • Not involving the quickest, shortest, or most convenient path 

noun
  • An indirect cost. 

  • An indirect radiator 

verb
  • To access by means of indirection; to dereference. 

perpendicular

adj
  • at or forming a right angle (to something). 

  • Exactly upright; extending in a straight line toward the centre of the earth, etc. 

  • Independent of or irrelevant to each other; orthogonal. 

noun
  • A line or plane that is perpendicular to another. 

  • A device such as a plumb line that is used in making or marking a perpendicular line. 

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