no-facili verba

I just learned the word “no-facili”. This word is u forti no-facili verba. Did I say “very rude word” or “very difficult word”. There doesn’t seem to be an umbrella concept here. If I force an umbrella concept I get the word “rude” because rudeness is difficult but difficulty is not always the result of rudeness. This reasoning leads me to think “no-facili” means “rude to the point of difficulty”.

However, “facili” simply means “easy”, thus “no-facili” must really mean “difficult” and not “rude”. Does anyone know what to make of this?

Gratia, bill