1. To preoccupy the mind to the exclusion of other thoughts or feelings: Jack was prepossessed and consumed with sorrow of losing his wife in the car accident.
2. To influence beforehand against or in favor of someone or something; to prejudice: Joan's mother was quite biased and prepossessed of her daughter being the most beautiful girl in her class at school.
3. To impress favorably in advance or beforehand: Seeing the young and beautiful violist on stage prepossessed the audience even before she started playing!