In my personal definition, in a Rodeo 5, there will be a point where the line between your tips and tails passes 360 again. In a Lincoln 180, Underflip, Backflip 180, Flare, whatever you call it, they dont.
Here:
Rodeo 5:
http://media.nscdn.com/uploads/member/videos/MikeHelligan-Rodeo5Mute.wmv
Tips and tails point 360 when the video does the flashy thingy.
The Underflarebacklincoln180:
http://media.nscdn.com/uploads/member/videos/1163034511Nikklas.mov
Niklas here does a really good example of what I'm talking about. His tips never come to 360, always staying towards the camera.