Yeísmo

Yeísmo (Spanish pronunciation: [ɟʝeˈizmo]) is a distinctive feature of many dialects of the Spanish language, which consists of the loss of the traditional palatal lateral approximant phoneme /ʎ/ (written ⟨ll⟩) and its merger into the phoneme /ʝ/ (written ⟨y⟩), usually realized as a palatal approximant or affricate. It is an example of delateralization.

In other words, ⟨ll⟩ and ⟨y⟩ represent the same sound /ʝ/. The term yeísmo comes from the Spanish name of the letter ⟨y⟩ (ye). Now, over 90% of Spanish dialects exhibit this phonemic merger. Similar mergers exist in other languages, such as Italian, Hungarian, Catalan, Portuguese or Galician, with different social considerations.

Occasionally, the term lleísmo (pronounced: [ʎeˈizmo]) has been used to refer to the maintenance of the phonemic distinction between /ʝ/ (spelled "y") and /ʎ/ (spelled "ll").

Most dialects that merge the two sounds represented by ⟨ll⟩ and ⟨y⟩ realize the remaining sound as a voiced palatal fricative [ʝ], which is similar to the ⟨y⟩ in English your, but it sometimes sounds like ⟨j⟩ in English jar, especially after /n/ or /l/ or at the beginning of a word. For example, relleno is pronounced [reˈʝeno] and conllevar is pronounced [koɲɟ͡ʝeˈβaɾ] or [koɲdʒeˈβaɾ].

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