1. when a situation is so sad and unhappy , it represents a sad semi-flaccid erection 2. the act of having a sad, semi-flaccid erection

Example One:Bro1: -texts bro2- Wanna go get some chinese?Bro2: -responds- Can't, gotta work til midnight.Bro1: Sad boner Example Two:Girlfriend: I don't think you should come stay over tonight, It's that time of the month -Boyfriend, having an actual sad boner , responds "Sad boner"-