A guy who seems sweet and kind because he flirts and gives you unwarranted attention, but who is actually a creepy predator/pervert on the prowl for some new (usually young) girl of whom he can take advantage. A groundhog spends the majority of their time being an underground gets labeled as such because of the amount of time they remain underground sleezes. The best defense against groundhogs is to chase them out of their holes and expose them.
When a senior football player flirts with a freshman cheerleader, he is a groundhog.
by ynotnvme November 18, 2011
The point of having to poop so bad that it starts peeking out of your butthole, like a groundhog peeking out if it's hole, and you have to squeeze it back in to hold it until you get the restroom.
I started groundhog in the store and barely made it to the restroom before pooping my pants.
by Titten from Phoenix February 27, 2009
An out of shape person who joins a gym or exercise class in early January as a New Year's resolution to lose weight. They give a half-hearted effort for a few weeks and by February 2nd ( Groundhog Day ) they haven't realized any loss of weight or size and become disenchanted and give up.
" It really sucks to go to the gym in January because of all the GROUNDHOGS in there using all the equipment and standing around talking crap. That's okay, because when February 2nd rolls around they still see their fat shadow and they get scared and run away from the gym and leave the rest of us in peace. "
by Electrian January 15, 2012
The tragic incident in which the small piece of skin on the underside of ones penis breaks in half causing immense pain. This is usually caused by roughly brushing the penis on the ground after intercourse.
Holy shit man! Another groundhog? You gotta start doing it on the bed instead!
by k0mmand0 April 07, 2004