Voiced dental fricative

Voiced dental fricative
IPA Number131
Entity (decimal)ð
Unicode (hex)U+00F0
Braille⠻ (braille pattern dots-12456)
Audio sample
Voiced dental approximant

The voiced dental fricative is a consonant sound used in some spoken languages. It is familiar to English-speakers, as the th sound in father. Its symbol in the International Phonetic Alphabet is eth, or [ð] and was taken from the Old English and Icelandic letter eth, which could stand for either a voiced or unvoiced interdental non-sibilant fricative.

The letter ⟨ð⟩ is sometimes used to represent the dental approximant, a similar sound, which no language is known to contrast with a dental non-sibilant fricative,[1] but the approximant is more clearly written with the lowering diacritic: ⟨ð̞⟩. Very rarely used variant transcriptions of the dental approximant include ⟨ʋ̠⟩ (retracted [ʋ]), ⟨ɹ̟⟩ (advanced [ɹ]) and ⟨ɹ̪⟩ (dentalized [ɹ]). It has been proposed that either a turned ⟨ð⟩ or reversed ⟨ð⟩ be used as a dedicated symbol for the dental approximant, but despite occasional usage this has not gained general acceptance.[2] Dental non-sibilant fricatives are often called "interdental" because they are often produced with the tongue between the upper and lower teeth (as in English), and not just against the back of the upper teeth, as they are with other dental consonants.

This sound and its unvoiced counterpart are rare phonemes. Almost all languages of Europe and Asia, such as German, French, Persian, Japanese, and Mandarin, lack the sound. Native speakers of languages without the sound often have difficulty enunciating or distinguishing it, and they replace it with a voiced alveolar sibilant [z], a voiced dental stop or voiced alveolar stop [d], or a voiced labiodental fricative [v]; known respectively as th-alveolarization, th-stopping, and th-fronting. As for Europe, there seems to be a great arc where the sound (and/or its unvoiced variant) is present. Most of Mainland Europe lacks the sound. However, some "periphery" languages as Gascon, Welsh, English, Icelandic, Elfdalian, Kven, Northern Sami, Inari Sami, Skolt Sami, Ume Sami, Mari, Greek, Albanian, Sardinian, some dialects of Basque and most speakers of Spanish have the sound in their consonant inventories, as phonemes or allophones.

Within Turkic languages, Bashkir and Turkmen have both voiced and voiceless dental non-sibilant fricatives among their consonants. Among Semitic languages, they are used in Turoyo, Modern Standard Arabic, albeit not by all speakers of modern Arabic dialects, as well as in some dialects of Hebrew and Assyrian Neo-Aramaic.


Features of the voiced dental non-sibilant fricative:

  • Its manner of articulation is fricative, which means it is produced by constricting air flow through a narrow channel at the place of articulation, causing turbulence. It does not have the grooved tongue and directed airflow, or the high frequencies, of a sibilant.
  • Its place of articulation is dental, which means it is articulated with either the tip or the blade of the tongue at the upper teeth, termed respectively apical and laminal. Note that most stops and liquids described as dental are actually denti-alveolar.
  • Its phonation is voiced, which means the vocal cords vibrate during the articulation.
  • It is an oral consonant, which means air is allowed to escape through the mouth only.
  • It is a central consonant, which means it is produced by directing the airstream along the center of the tongue, rather than to the sides.
  • The airstream mechanism is pulmonic, which means it is articulated by pushing air solely with the lungs and diaphragm, as in most sounds.
Other Languages
Bahasa Melayu: Geseran gigi bersuara
中文: 濁齒擦音