1 definition by GirlUpstairs

A man or woman dedicated to improving the physical fitness of others through the implementation of a rigorous workout schedule. Because of their well toned bodies, they are often the target of many sexual advances.
Girl 1- "Hey, do you think that new girl in spin class is really here for the workout?"

Girl 2- "No way, she totally came to throw herself at our buff fitness instructor. How sad."
by GirlUpstairs April 27, 2009
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