Sulcalization

In articulatory phonetics, sulcalization (from Latin: sulcus 'groove') is the pronunciation of a sound with a deep, longitudinal concavity (groove) down the back of the tongue (the dorsum), roughly opposite of the uvula. This is accomplished by raising the sides of the dorsum, and leaving a hollow along the mid-line.

This articulation has typically been associated with rhotics such as a 'bunched' or 'molar' [ɹ̈] and r-colored vowels, as well as 'dark' or 'throaty' quality sounds, either more velar-like (such as [ɫ]) or more pharyngeal-like (such as [ɒ]).

No spoken language is known to make a phonemic distinction between sulcalized and ordinary vowels; though it has been reported that for some speakers of Received Pronunciation, the vowel /ɒ/, which is normally described as rounded, is pronounced with neutral or spread lips, and is instead given its characteristic quality through a "hollowing or sulcalization of the tongue-body." One scholar has also suggested that the vowel in the RP pronunciation of words like bird, typically transcribed /ɜː/, is actually a sulcal schwa, retaining the sulcality of the original rhotic consonant. Accordingly, the realization of the /ə/-element of the centring diphthongs /ɪə̯/, /ʊə̯/, /ɛə̯/ in words such as near, pure and scare, is interpreted as the product of a loss of sulcality. Similarly, it has been noted that the rhotacized equivalent [ɝ] in American English is sulcalized.