Fonotaktika

Fonotaktika, or phonotactics, is the branch of linguistics that studies the permissible combinations of sounds in a language. It describes how consonants and vowels may be arranged into syllables and what sequences are allowed or disallowed within words. Phonotactic knowledge helps speakers predict likely word shapes and guides the pronunciation of unfamiliar words.

A central focus is the syllable structure, including the roles of onset, nucleus, and coda, and which consonant clusters can occur at the beginning or end of a syllable. Languages differ widely in their constraints. Some favor relatively simple syllables (for example, CV or CVC in many languages), while others permit more complex onsets and codas.

Examples illustrate variation across languages. English allows several onset clusters, such as sp-, str-, and complex codas like -nd or -ct, whereas some languages restrict syllables to fewer consonants or forbid certain clusters. Japanese, by contrast, typically uses syllables that are CV or V, with limited coda consonants, making loanword adaptation more constrained. Diphthongs and triphthongs are common in many European languages, whereas some languages treat vowel sequences as separate syllables rather than as part of a single nucleus.

Phonotactics interacts with phonology and morphology and influences loanword adaptation, speech perception, and language learning. Phonotactic constraints are often described with rules, descriptive tables, or computational models, and are a key part of typological comparisons between languages.