Iotation

In Slavic languages, iotation (/joʊˈteɪ.ʃən/, /ˌaɪ.oʊˈteɪ.ʃən/) is a form of palatalization that occurs when a consonant comes into contact with the palatal approximant /j/ from the succeeding phoneme. The /j/ is represented by iota (ι) in the early Cyrillic alphabet and the Greek alphabet on which it is based. For example, ni in English onion has the sound of iotated n. Iotation is a phenomenon distinct from Slavic first palatalization in which only the front vowels are involved, but the final result is similar.