1. Think rationally; employ logic or reason
   "When one wonders why one is doing certain things, one should rationalise";
   - rationalize
    
2. Defend, explain, clear away, or make excuses for by reasoning
   "rationalise the child's seemingly crazy behaviour";
   - excuse, rationalize
    
3. Structure and run according to rational or scientific principles in order to achieve desired results
   "We rationalised the factory's production and raised profits";
   - rationalize
    
4. (mathematics) remove irrational quantities from
   "This function can be rationalised";
   - rationalize
    
5. Remove unnecessary or unwanted parts to improve efficiency or effectiveness
   "The company rationalised its production process";
   - cut, prune, rationalize

Derived forms: rationalised, rationalising, rationalises

Type of: alter, cerebrate, change, cogitate, defend, do away with, eliminate, extinguish, get rid of, modify, organise [Brit], organize, support, think

Encyclopedia: Rationalise