Liaison (French)

Liaison (French pronunciation: [ljɛ.zɔ̃]) is the pronunciation of a latent word-final consonant immediately before a following vowel sound. Technically, it is a type of external sandhi, which is disrupted in pausa.

In French, most written word-final consonants are no longer pronounced and are known as latent or mute. For example, the letter s in the word les, 'the', is generally silent (i.e., dead and phonologically null), but it is pronounced /z/ in the combination les amis /le.z‿a.mi/, 'the friends'. In certain syntactic environments, liaison is impossible; in others, it is mandatory; in others still, it is possible but not mandatory and its realization is subject to wide stylistic variation.

Liaison operates in word sequences whose components are closely linked by sense, e.g., article + noun, adjective + noun, personal pronoun + verb, and so forth. This would seem to indicate liaison is primarily active in high-frequency word associations (collocations). Liaison is a form of vestigial enchainement since both involve a follow-through between a final consonant (though otherwise mute in liaison) and an initial vowel. However, what is particularly distinct for both liaison and enchainement is that the final consonant in both cases re-syllabifies with the following vowel. Liaison is therefore an external sandhi phenomenon, that is, a phonological process occurring at word boundaries. Specifically, it is a form of consonant epenthesis and generally, though not always, involves resyllabification.

Like elision (as in *je aime → j'aime), it can be characterized functionally as a euphonic strategy for avoiding hiatus. If we look at it like this, we are adopting a synchronic approach. This approach does not explain cases where the first word already ends in a consonant, such as tels‿amis, and is therefore already perfectly euphonic.

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