A term used used to describe how your balls might smell, typicaly after walking around in the heat all day.
Damn bro its fucking hot out, I probably got a bad case of onion balls right now.
by MKasper August 09, 2006
1 more definition
When your balls are so sweaty and smelly they could make someone's eyes tear.
I went for a jog then I laid in the sun for an hour. My girl insisted on giving me head, her eyes started tearing up and then I told her I had a bad case of Onion balls.
by miggelzworth October 26, 2010