Synonyms for Rationalize (same or very similar meaning)
WordNet sense 1 (structure and run according to rational or scientific principles in order to achieve desired results):
rationalise
WordNet sense 2 (defend, explain, clear away, or make excuses for by reasoning):
apologize, excuse, justify, apologise, excuse
WordNet sense 3 (weed out unwanted or unnecessary things):
cut, prune
From the ODE community, based on WordNet
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