A common trick of the trade in script writing: say a word most people have never heard. Let it roll off the tongue of the actor glibly like he or she always knew it and assumed everyone else did as well.
Think about it next time you're watching a movie. Try to find a word in the movie that is
b. newly invented, or
The way it is said and repeated throughout the movie tends to make the audience want to say it as well. Chances are by the time the movie ends you will have mouthed it once or twice. You will bring it up in conversation within the next few days because it has now become a part of your current speaking vocabulary.
Everyone has three vocabularies: a reading vocabulary, a writing vocabulary, and a speaking vocabulary. Your reading vocabulary consists of the words you can understand when you read them. Your writing vocabulary is made of the words you can think of when you're writing. Your speaking vocabulary is the smallest of the three. It changes over time. Some words that are overused are dropped from it and fresh words are added as they are heard from other people, read in books, or mentioned in a movie.
Write on! No copyrights here! Invent some words or dust off something retro. Get to it!