Computer science has only had about 50 years to develop - we may have seen our Issac Newtons and Leibniz's but once we have 200 years of Gausses and Riemann's there'll be a lot of additional abstraction that's implicit depending on which subset of study you choose. CS will fork off into various subsets just like any other formal science, and a greek symbol to someone who finished their PhD in complex analysis might mean something entirely different to someone who's been working specifically in combinatorics for 30 years. At that point, our level of abstraction won't be pieces of paper on a stack.
It's not exclusive to CS or mathematics, ask someone who hasn't taken O-chem what "R" means in a Lewis Diagram. Ask a non-linguistic (of either type (ugh pun not intended)) what a 'terminal symbol' is. I'm sure they'll answer differently from someone who works at the airport, that's for sure.