rationalise

1. structure and run according to rational or scientific principles in order to achieve desired results;

"We rationalized the factory's production and raised profits"

2. defend, explain, clear away, or make excuses for by reasoning;

"rationalize the child's seemingly crazy behavior"

"he rationalized his lack of success"

3. think rationally; employ logic or reason;

"When one wonders why one is doing certain things, one should rationalize"

4. remove irrational quantities from;

"This function can be rationalized"

5. weed out unwanted or unnecessary things;

"We had to lose weight, so we cut the sugar from our diet"