Buck Vu, a character from the series The OA. A Vietnamese-American transgender high school student that helps The OA on her journey along with 4 other people from his school. Played by Ian Alexander.
Buck is used as a nickname for the dead son, Jordan Jarret, in Ordinary People by Judith Guest. I really don't know how Buck is short for Jordan though. However, I agree with Slight Night Shiver, it really does sound like a hillbilly name. If you are insistent on calling your son Buck, I would recommend just using it as a nickname. It's so tacky and unprofessional sounding.