ineffable - Dictionary definition and meaning for word ineffable
IN+ F(eff) + able--You cannot utter the letter F*** everywhere.There are places where it is unutterable.:)
In Eff :In Eiffel tower,you feel great joy to visit it that you can't describe in words
She is an AFFABLE(friendly) but INEFFABLE (cant describe) beauty
effe sounds like affe (monkey), which stands for something undescribable, taboo, or beyond expression.