Someone who is shit on and ultimately will go fucking insane. at the workplace, this person is usually withdrawn and very quiet. but little do you know, this person hates everyone and everything at his workplace and is one unhappy mother fucker. his is imprisoned to his job and cannot leave his job security due to finicial responsibilities, drug habits, kids etc. so when kept in the 9-5pm cage he plots and plans how he will go off on the next shit talkin mother fucker. a disgruntled employee, usually steals stuff from his workplace according to his " fuck or be fucked" motto or fuck the company before they fuck you. a great example of a disgruntled employee, if you watch DISTURBED'S VOICES music video. Disgruntled employees are highly dangerous no matter what they look like or how big or small they are. leave them alone in the best interest of your safety.
John walks in to the corporate office with headphones on, on his way to his cubicle.(you can hear blasting on his headphones) "let the bodies hit the floor, let the bodies hit the floor, let the bodies hit the, (2 cymbal clashes) FFFFLLLLLOOOOORRRRRR!!!!!!!!!!!!" ted the newly promoted district manager smirks at john. john then grabs ted by the shirt and punches him in the face and knocks him out. and continues to ruin and break shit as he's beating the shit out of people. he makes it to his cubicle and starts his accounting work as people stare at him. now thats a disgruntled employee!