quadratic vs rectangular

quadratic

adj
  • square-shaped 

  • of a function, of the form y=ax²+bx+c. 

  • of a polynomial, involving the second power (square) of a variable but no higher powers, as ax²+bx+c. 

  • of an equation, of the form ax²+bx+c=0. 

noun
  • A quadratic polynomial, function or equation. 

rectangular

adj
  • Having a shape like a rectangle. 

  • Having axes that meet each other with right angles. 

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