Alveolar ridge

An alveolar ridge (/æl.ˈvi.ə.lər/ or /æl.ˈvi.lər/; also known as the alveolar margin) is one of the two jaw ridges either on the roof of the mouth between the upper teeth and the hard palate or on the bottom of the mouth behind the lower teeth. The alveolar ridges contain the sockets (alveoli) of the teeth. They can be felt with the tongue in the area right above the top teeth or below the bottom teeth. Its surface is covered with little ridges.

Consonants whose constriction is made with the tongue tip or blade touching or reaching for the alveolar ridge are called alveolar consonants. Examples of alveolar consonants in English are, for instance, [t], [d], [s], [z], [n], [l] like in the words tight, dawn, silly, zoo, nasty and lurid. There are exceptions to this however, such as speakers of the New York Accent who pronounce [t] and [d] at the back of their teeth. When pronouncing these sounds the tongue touches ([t], [d], [n]), or nearly touches ([s], [z]) the upper alveolar ridge, which can also be referred to as gum ridge. In many other languages, consonants transcribed with these letters are articulated slightly differently, and are often described as dental consonants. In many languages consonants are articulated with the tongue touching or close to the upper alveolar ridge. The former are called alveolar plosives, and the latter alveolar fricatives.

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