Because he doesn't believe the definitions in the dictionary. He's said so many times. How can you have a conversation when the other party doesn't believe what the words mean? I don't live on that planet. Only he does. Then he keeps saying no one can tell him he's wrong because all the counterarguments you present are swept away by him with a simple "it's MSM, all lies".
So I reply with the "read a dictionary" every time he posts one of his long diatribes full of links to conspiracy websites.
Does that fill in the missing part?