What is the meaning of stomach-spinning rides?

rides

3. A device, such as one at an amusement park, that one rides for pleasure or excitement.

http://www.thefreedictionary.com/rides

stomach-spinning 反胃

D RIDES 可以轉到人反胃，當然是指遊樂場機動遊戲，不過，講坐交通工具也可以。

1. The act or an instance of riding, as in a vehicle or on an animal.

http://www.thefreedictionary.com/rides

... the official convertible of my east coast adventures, and we headed to the land of sunshine and stomach spinning turbulence. ... Many of the rides required 48 or 54 inches of height, thereby saving them money on child-seats. ...
www.divamind.com/ian/L081000.htm - 26k

As the flashback kicks in you see yourself frantically shuffling the kids from theme park to theme park where you wait in line an average of 2 hours in sweltering 90۫ heat just to get on rides that send your stomach spinning and your ...
www.4parentsnetwork.com/ jump.asp?channel=1&id=741&t=l - 26k