foräänenmuokkautus
Foräänenmuokkautus is a Finnish term that translates to "vowel harmony" in English. It refers to a phonological process in the Finnish language where vowels within a word must belong to the same class. There are two main classes of vowels in Finnish: front vowels (ä, ö, y) and back vowels (a, o, u). Vowel harmony applies to most Finnish words, although there are exceptions and loanwords that do not fully adhere to the rule.
The principle of vowel harmony affects the pronunciation and morphology of Finnish words. Suffixes in Finnish
There are also neutral vowels (i, e) that can appear in words with either front or back