ra·tion·al·ize / ˈrashənlˌīz; ˈrashnəˌlīz/ • v. [tr.] 1. attempt to explain or justify (one's own or another's behavior or attitude) with logical, plausible reasons, even if these are not true or appropriate: she couldn't rationalize her urge to return to the cottage.2. make (a company, process, or industry) more efficient by reorganizing it in such a way as to dispense with unnecessary personnel or equipment: his success was due primarily to his ability to rationalize production.3. Math. convert (a function or expression) to a rational form.DERIVATIVES: ra·tion·al·i·za·tion / ˌrashənl-əˈzāshən; ˌrashnələ-/ n.ra·tion·al·iz·er n.