Rationalise
Part of speech: verb
Definition: To make something rational or more rational.
Rationalize
Part of speech: verb
Definition: To make something rationalTo justify an immoral act, or illogical behaviour. “The process of thought by which one justifies a discreditable act, and by which one offers to oneself and the world a better motive for one's action than the true motive”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.
Example sentence: Man can and does rationalize his sins. He finds reasons for all his weakness, invents excuses that first calm and then deaden his conscience. He blames God, society, education, and environment for his wrong doing.