I vaguely recall a story that quiz was a word invented by an Irishman to fulfill a bet that he could get people to use a new word. He put posters up all over Dublin inviting people to a quiz. People then had a quiz between themselves as to what a quiz was. I can't recall the details and this may just be a story but it's a possible way to get a new word into the dictionary fairly quickly.

By the way L. O. C. is a standard medical abbreviation for loss of consciousness, not lack of concentration which is much more poetically described by the term lackadaisical.