The ability to resist any minor sickness / cold after an extended time living in a frat house. The frat house basically serves as an innoculation for various diseases. The innoculation period usually lasts 3 months upon entry to the frat house, where you will generally feel like crap, be sick all the time etc... but afterwards you will have earned your fratolerance.

A person with an outwardly dominant, masculine, or aggressive personality, but who also enthusiastically takes on the submissive or "bottom" role in the bedroom.