It's funny how things seem to you on one hand, and how those exact same things can seem to someone else. When I was younger I used to wonder whether my concept of the colour yellow, for example, was the same as everyone else's. Did they see yellow as I saw yellow? Was what I thought of as yellow in fact red to someone else? The same with words. Where you see or hear the same word so often you begin to forget its meaning, or you can no longer tell if it's even a real word.