ineffable - Dictionary definition and meaning for word ineffable
in+ef+ fable. fable means story. story can be told. in-fable means something which can not be uttered such as the name of Lord Voldemort (from Harry Potter).
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.