The word stays the same, but the meaning keeps changing. The meaning of freedom won't stay still. Look back at the other examples I gave you, and you'll see the same sorts of problems. We need to talk about ideas and concepts, and we need terms that represent them. But we must understand how imprecise their meanings are, how easily they can be differently understood, and how tiring and boring long chains of abstract terms can be.
Concrete terms refer to objects or events that are available to the senses.
Examples of concrete terms include spoon, table, velvet eye patch, nose ring, sinus mask, green, hot, walking . Because these terms refer to objects or events we can see or hear or feel or taste or smell, their meanings are pretty stable. If you ask me what I mean by the word spoon , I can pick up a spoon and show it to you. While abstract terms like love change meaning with time and circumstances, concrete terms like spoon stay pretty much the same. Spoon and hot and puppy mean pretty much the same to you now as they did when you were four.