FIXATED definition: 1. unable to stop thinking about something: 2. unable to stop thinking about something: 3…. Learn more. Definition of fixated adjective in Oxford Advanced Learner's Dictionary. Meaning, pronunciation, picture, example sentences, grammar, usage notes, synonyms and more. If you fixate on something, you become overly focused on it or attached to it. Don't fixate on your grades — try to enjoy the process of learning! GMass allows you to easily schedule emails, send out mass emails and mail merge campaigns and more with Gmail! Click here to learn about more features!