As I said above, I think I kind of misphrased my question while trying to make it clear in my head - almost ironically, my inability to find the right words hampered my ability to communicate what I meant.

I agree completely about people making up words for new ideas - I suppose that's what I meant to bypass: we make up words as shorthand for longer concepts, because if we didn't, it would take a lot longer to say or explain what we meant. My question was meant to be along the lines of, if we didn't have those new words, would our rationality be hampered by the lack of specific words (even if we knew what we meant in our minds)? (You don't have to answer that, I was just trying to clarify!)