Ra"tion*al*ize (răsh"ŭn*al*īz), v. t. 1. To make rational; also, to convert to rationalism.

2. To interpret in the manner of a rationalist.

3. To form a rational conception of.

4. (Alg.) To render rational; to free from radical signs or quantities.

Ra"tion*al*ize, v. i. To use, and rely on, reason in forming a theory, belief, etc., especially in matters of religion: to accord with the principles of rationalism.

Theodore . . . is justly considered the chief rationalizing doctor of antiquity.

• to make something rational
  
• to justify an immoral act, or illogical behaviour
  
• (mathematics) to remove radicals , without changing the value of an expression or the roots of an equation
  
• to structure something along modern, efficient and systematic lines, or according to scientific principles