hääletu

Hääletu is a term used in phonetics and linguistics to describe sounds that are produced without vibration of the vocal cords. It is the opposite of voiced sounds, which involve vocal fold vibration during articulation. In languages that contrast voiceless and voiced consonants, hääletu refers to the subset of sounds that are produced with an open glottis and no periodic vocal vibration.

Most commonly, hääletu describes consonants, such as certain plosives and fricatives, but the concept applies to any sound category that can be distinguished by voicing. The presence or absence of voicing affects how a sound is perceived and how it interacts with surrounding sounds in a language. In formal descriptions, hääletu is often represented by a feature value such as [−voice] in phonological analysis or IPA notation.

In Estonian linguistic usage, hääletu is used to classify consonants and to discuss contrasts with voiced consonants. Owing to the fact that writing in Estonian does not mark voicing explicitly in the orthography, the determination of whether a consonant is hääletu or hääldatud (voiced) relies on pronunciation and phonological description rather than spelling alone.

The concept is cross-linguistic and relevant for language learning, transcription, and phonological theory. In the International Phonetic Alphabet (IPA), voiceless sounds are described with the feature [−voice], and many languages employ both hääletu and voiced consonants to create distinct lexical or grammatical contrasts.