i'm an RN. years ago i worked in at an infusion (intravenous therapy) home health company. previous to that job, i worked at a large hospital as an "infusion RN", on the IV Team. when i went to work in Home Health i had tons more IV experiance than anyone else there. if someone needed an IV and no one else could get an IV started, they'd call me. pretty soon the other nurses there started calling me 'The Jacman'. kinda like Superman. the 'the' got dropped, and everone started calling me jacman, and the name stuck. i work at another company now, but several of the folks from the first company work there also, so now everyone at the new place calls me jacman, too.