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The voiced alveolar sibilant is common across European languages, but is relatively uncommon cross-linguistically compared to the voiceless variant. Only about 28% of the world's languages contain a voiced dental or alveolar sibilant. Moreover, 85% of the languages with some form of are languages of Europe, Africa, or Western Asia.
The voiced alveolar non-sibilant fricative is a consonantal sound. As the International Phonetic Alphabet does not have separate symbols for the alveolar consonants , it can represent the sound as in a number of ways including ⟨ð̠⟩ or ⟨ð͇⟩ , respectively], ⟨ɹ̝⟩ ], or ⟨d̞⟩ ].
Few languages also have the voiced alveolar tapped fricative, which is simply a very brief apical alveolar non-sibilant fricative, with the tongue making the gesture for a tapped stop but not making full contact. It can be indicated in the IPA with the lowering diacritic to show that full occlusion does not occur. Flapped fricatives are theoretically possible but are not attested.