In Slavic languages, iotation (IPA [joʊˈteɪʃən]) is a form of palatalization which occurs when a consonant comes into contact with a palatal approximant /j/ from the succeeding morpheme. The sound /j/ is represented by iota (ι) in the Cyrillic alphabet and the Greek alphabet it is based on, hence the name. For example, ni in English onion has the sound of iotated n. Iotation is a distinct phenomenon from Slavic first palatalization (in which only the front vowels are involved), although the end result is similar.

In Slavic languages, iotation (IPA [joʊˈteɪʃən]) is a form of palatalization which occurs when a consonant comes into contact with a palatal approximant /j/ from the succeeding morpheme. The sound /j/ is represented by iota (ι) in the Cyrillic alphabet and the Greek alphabet it is based on, hence the name. For example, ni in English onion has the sound of iotated n. Iotation is a distinct phenomenon from Slavic first palatalization (in which only the front vowels are involved), although the end result is similar.