I didn't see it myself — I was busy driving to New Jersey, which would make anyone gruntled — but apparently "The Office" took a page from this blog last night. (Spoilers follow if you missed it.) In an episode entitled "The Negotiation," Roy attempts to attack Jim (your typical office-romance-love-triangle-workplace-violence story) and gets pepper-sprayed by Dwight. Later, Michael is discussing the incident with Jan:
It was a crime of passion, Jan, not a disgruntled employee. Everyone here is extremely gruntled.
If TV says it's a word, who am I to argue?