A very hard rainstorm that brings a lot of rain in a short amount of time. Unlike a hurricane that covers vast amounts of area, a gullywhumper typically refers to a local thunderstorm that turned severe with the rainfall.
Gullywhumpers typically have heavy flooding and standing water in places that normally are dry or drain very quickly after a storm. ie The 100 Year Flood.
That storm last night was a real Gullywhumper. It rained 6 inches in 2 hours! Bullfrog Creek is still flooding over the road.
A made up fictional monster that Author, Judy Miceli, wrote about in her book "Scaring Bryan!" That would come out at night and attack children who would not listen to their mothers.
1) The thing that hangs down from a turkey's neck.
2) Also used to refer to the thing that hangs from an obese person's neck. Especially if a person was obese, lost weight, and has loose extra skin.
3) Can sometimes be used in reference to the male genetalia.
4) Walt.
(3) female: "So, me and this guy were foolin around and his gollywhopper was huge, so I could only give him a helmet wash, but then he spiderman'd me!