askew vs perpendicular

askew

adj
  • Turned or twisted to one side. 

  • Untoward, unfavourable. 

adv
  • Tilted to one side. 

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 askew and perpendicular occurred in a corpus of books? (source: Google Ngram Viewer )