Approximantteihin

Approximantteihin is a Finnish-form term used in linguistics to refer to the class of approximant sounds. In phonetics, approximants are consonants produced with a narrow constriction of the vocal tract that is not tight enough to cause turbulent airflow. They are typically voiced and behave as sonorants, falling between vowels and obstruent consonants in terms of constriction and airflow.

Articulation and typology tend to distinguish two broad groups. Central approximants occur with the constriction in the central part of the vocal tract and include sounds like the palatal approximant [j] (as in yes) and the labio-velar approximant [w] (as in wet). Lateral approximants, such as the alveolar lateral [l], involve a constriction along the sides of the tongue. Many languages further diversify these into velar, palatal, alveolar, retroflex, and other variants, and some also report rhotic approximants (a family of central sounds with varying placement and articulation). While the most familiar approximants in English are [w], [j], and [l], a wide cross-linguistic inventory exists.

Distribution and phonology vary by language. Approximants often appear in syllable onsets and can occur in codas or even function as syllabic elements in some languages. They contrast with vowels, fricatives, nasals, and plosives in both articulation and phonotactic behavior, yet they share the property of being relatively vowel-like in their lack of strong turbulent noise. In many descriptive traditions, approximants are treated together with glides or liquids as a broad class of sonorant consonants, with language-specific realizations shaping their exact phonetic profile.