"What's a shank?"
Thomas almost—almost—laughed. An irrational response that somehow would've seemed appropriate. (26.44)
In Maze Runner,the Gladers were all placed in a Maze where they had to build their own civilization. A unique jargon was pretty much bound to arise. If you're building up an entirely new civilization on your own—and your memories have pretty much been wiped—it's almost inevitable that you're going to have to come up with new words for things.
Though it's not a huge factor, vocabulary seems to link the boys who survived throughout the Maze together. Saying things like "shuck" and "klunk" are just ways these kids can fit in with one another. If they talk the same, then that's one way of becoming more unified.
At first, Thomas is pretty confused about the jargon, but eventually it becomes second nature to him. It's just like when you start a new job or join a team: at first, you need to think of what certain words mean. If you're a runner, you'll eventually understand what a tempo run is and what lactate threshold means; it just becomes part of your vocabulary. If you work in the field of dentistry, things like gingival inflammation and lingual tori are just common words.
Just take a look at what Aris calls the boys:
"Then you sticks show up."
"Sticks?" Minho repeated ...Minho exchanged a glance with Thomas, half smiling. Looked like both groups had come up with their own vocabulary. (6.16)
Building a unique jargon is an intrinsic quality of humans, and it brings us together. So listen up and start acting like a shank, klunkheads.