Cluster reduction

In phonology and historical linguistics, cluster reduction is the simplification of consonant clusters in certain environments or over time.

In some dialects of English such as AAVE certain historical consonant clusters reduce to single consonants at the ends of words: friend rhymes with Ben, and cold is homophonous with coal. In both cases, a historical cluster of homorganic consonants loses a stop: /ˈfrɛn/, /ˈkoʊl/ However, in colder, where the consonant cluster falls between vowels, the /d/ remains: /ˈkoʊldɚ/. The similar word-final reduction of */mb/ to /m/ and */ŋɡ/ to /ŋ/ is complete in standard English (e.g. lamb, long), as it is in many other Germanic languages (e.g. Swedish lamm, lång).

Italian is well known to have undergone cluster reduction, where stop clusters have become geminates. For example, Victoria has become Vittoria. In other words, articulation but not length has reduced. A similar occurrence is observed in Portuguese as well, but gemination is absent. Cluster reduction also takes place in Catalan, and in a similar way as it happens in English. Certain consonant clusters placed at the end of a word are reduced: cent /sen/ instead of /sent/, although they recover the reduced consonant when the cluster falls between vowels: centenar /səntəˈna/. This phenomenon does not exist in Valencian, though: cent /sent/ and centenar /senteˈnaɾ/.

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