At least four men performing sexual penetrating acts (anal, oral, salad-tossing, etc.) with each other, all connected to make a complete circle (e.g. wheel).
The circle jerk is so 80's! Today it's all about the man-wheel.
A cart wheel done in a way where it looks rigid, amateurish with legs and body stiff and bent. Males usually can't do cart wheels as nice as girls in general, so when they attempt this technique it's called a Man-Wheel, due to most males not knowing how to do nice look cart wheels, but the term gives them an ego boost.
That cheer leader maybe able to do nice cart wheels, but it is nothing compared to my awesome Man-Wheel!