The voiced dental fricative is a type of consonantal sound, used in some spoken languages. The symbol in the International Phonetic Alphabet that represents this sound is ð, and the equivalent X-SAMPA symbol is D. The dental fricatives are often called "interdental" because they are often produced with the tongue between the upper and lower teeth, and not just against the back of the teeth, as they are with other dental consonants.
Features
Features of the voiced dental fricative:
The voiced dental fricative occurs in English, and it is the sound denoted by the 'th' digraph in this and the. It is different from the sound represented by 'th' in thing and bath, which is the voiceless dental fricative.
In Old English, the letters þ and ð were used interchangeably for this sound and the voiceless dental fricative, but they have been dropped from modern usage in favour of the 'th' digraph. Although the same digraph is used for the voiced and voiceless forms, these sounds are not interchangeable in spoken English.
Other languages
Many commonly spoken languages, such as German, French, Japanese, and Chinese, lack this sound. Native speakers of those languages sometimes have difficulty enunciating or distinguishing it, and replace it with a voiced alveolar fricative or a voiced dental plosive.
Icelandic retains the letter ð for this sound.
Welsh uses the digraph 'dd' for this sound.
See also
