look up any word, like bae:
 
1.
a fine female specimen found near elliptical, treadmill, stair-stepper, or other calorie burning equipment. usually finely attired in roll-up shorts, sorostitute mixer shirts, and nike shox.
Dr. Swole pwned that cardio bunny on the elliptical.
by Billy Bong Thorton September 17, 2005
 
2.
Someone who spends time in a 'cardio' room, doing either elliptical, crosstrainer, or treadmill machines with no intensity, and ultimately make no progress. The worst offenders subsequently down a high-calorie beverage, completely negating their workout.
Jane: "Yeah, I hit the gym. I spend a half hour on a crosstrainer."

John: "Don't be a cardiobunny, put some intensity into your workout!"
by Timmy™ March 10, 2007
 
3.
Those cute girls that come dressed in skimpy attires wearing make up and going all out on the cock tease, wile pretending to be offended when unattractive males hit on them.
Their workout consists of only cardio routines. It is as if the weights are constantly out of reach for the cardiobunny.
Old school Lifter to power lifter: - Bro, that cardiobunny was on the treadmill for 3 hours straight, she must want the dick.
by mihaihen October 14, 2013