The voiceless alveolar, dental and postalveolarplosives (or stops) are types of consonantal sounds used in almost all spokenlanguages. The symbol in the International Phonetic Alphabet that represents voiceless dental, alveolar, and postalveolarplosives is ⟨t⟩, and the equivalent X-SAMPA symbol is t. The voiceless dental plosive can be distinguished with the underbridge diacritic, ⟨t̪⟩ and the postalveolar with a retraction line, ⟨t̠⟩, and the Extensions to the IPA have a double underline diacritic which can be used to explicitly specify an alveolar pronunciation, ⟨t͇⟩.
The [t] sound is a very common sound cross-linguistically.[1] Most languages have at least a plain [t], and some distinguish more than one variety. Some languages without a [t] are colloquial Samoan (which also lacks an [n]), Abau, and Nǁng of South Africa.[citation needed]
There are only a few languages which distinguish dental and alveolar stops, Kota, Toda, Venda and many Australian Aboriginal languages being a few of them; certain varieties of Hiberno-English also distinguish them (with [t̪] being the local realisation of the Standard English phoneme /θ/, represented by ⟨th⟩).
Its manner of articulation is occlusive, which means it is produced by obstructing airflow in the vocal tract. Since the consonant is also oral, with no nasal outlet, the airflow is blocked entirely, and the consonant is a plosive.
There are three specific variants of [t]:
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.
Denti-alveolar, which means it is articulated with the blade of the tongue at the alveolar ridge, and the tip of the tongue behind upper teeth.
Alveolar, which means it is articulated with either the tip or the blade of the tongue at the alveolar ridge, termed respectively apical and laminal.
Its phonation is voiceless, which means it is produced without vibrations of the vocal cords. In some languages the vocal cords are actively separated, so it is always voiceless; in others the cords are lax, so that it may take on the voicing of adjacent sounds.
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.
Laminal denti-alveolar. Likely to have allophones among native speakers, as it may affricate to [tʃ], [tɕ] and/or [ts] in certain environments. See Portuguese phonology
Usually transcribed in IPA with ⟨d̥⟩ or ⟨d⟩. Contrasts with the affricate [t͡s] or aspirated stop [tʰ] (depending on the dialect), which are usually transcribed in IPA with ⟨tˢ⟩ or ⟨t⟩.[37] See Danish phonology
Less often voiced [d]. It is usually transcribed /d/, and it contrasts with voiceless aspirated form, which is usually transcribed /t/.[41] See Luxembourgish phonology
Varies between laminal denti-alveolar and laminal alveolar. It is usually transcribed /d/. It may be partially voiced [d̥], and it contrasts with voiceless aspirated form, which is usually transcribed /t/.[48] See Norwegian phonology