Ze with diaeresis
Ze with diaeresis is a letter of the Cyrillic script. It is used only in the Udmurt language, where it represents the voiced [alveolo-palatal affricate]. It is usually romanized as ⟨đ⟩, but its ISO 9 transliteration is ⟨z̈⟩.
It was also formerly used in the Bashkir language, where it represented the voiced [dental fricative]. In this function, the letter has been replaced with dhe.