@Ragman,
Sale that past me again.
Although rationalize retains its principal 19th-century senses “to make conformable to reason” and “to treat in a rational manner,” 20th-century psychology has given it the now more common meaning “to ascribe (one's acts, opinions, etc.) to causes that seem reasonable but actually are unrelated to the true, possibly unconscious causes.” Although the possibility of ambiguity exists, the context will usually make clear which sense is intended.
verb
1.
to justify (one's actions, esp discreditable actions, or beliefs) with plausible reasons, esp after the event
2.
(psychol) to indulge, often unchallenged, in excuses for or explanations of (behaviour about which one feels uncomfortable or guilty)