In the Wheel of Time, naming the Dark One by his real name, Shai'tan, is considered dangerous because it draws his attention to you. Likewise for darkfriends; it is considered blasphemy so they don't say it either. If this is so, how does everybody know the name, because nobody wants to say it?
A few characters in the series do say it out loud, but how did they get to know it?
It seems very improbable that everyone knows the name but only one in a thousand or more will ever say it out loud.