- linguolabials (at the lips; may also count as labial consonants)
- interdentals (between the teeth)
- dentals (at the teeth)
- alveolars (at the alveolar ridge)
- postalveolars (at the hard palate)
A division orthogonal to this also applies: whether the tip or the blade of the tongue is used. The former are called apical, the latter laminal. With postalveolar consonants, a third possibility also applies: using the underside of the tongue. This is called subapical articulation, but usually the term retroflex is used instead, referring to the entire articulation (subapical postalveolar).
Actually employing any of these contrasts is not particularly common, especially outside of the system of sibilant consonants.
The IPA offers only a single basic series of coronal consonant symbols: /t d n s z ɬ ɮ ɹ l r ɾ/. Diacritics are used to specify the articulation. This same approach is used in most alternate systems.
Retroflexes are the major exception; these have a number of dedicated symbols /ʈ ɖ ɳ ʂ ʐ ɻ ɭ ɽ/. Postalveolar non-retroflex sibilants also have separate symbols /ʃ ʒ/, and there are even /ɕ ʑ/ for their palatalized versions.
Phonology of coronals
All known natural languages have coronal consonants. They form a plurality of the consonants in many, if not most languages.
Thanks to the flexibility of the front part of the tongue, many consonant contrasts that are difficult or impossible at other POAs crop up frequently among coronals. These include (in approximate descending order of coronalness correlation):
- Sibilant consonants, e.g. /s/ †
- Click consonants, e.g. /ǃ/
- Lateral consonants, e.g. /l/
- Rhotic consonants, e.g. /r/
- Affricate consonants, e.g. /ʤ/
- Palatalized consonants, e.g. /ɕ/
(† A subtype of fricatives.)