1. To ignore someone, sometimes completely and regard the individual as petty or insignificant
2. The act of standing someone up either by ignoring their phone calls, not returning their calls, or failing to meet social arrangements with the person due to being too busy for the person, lack of interest in the person, or the need to just be left alone.
1. Ever since Jessica found a new boyfriend she's been brushing off her ex, Tony.
2. Mike continued to brush off the unattractive girl that kept trying to study with him.