• WordNet 3.6
    • n assibilation pronunciation with a sibilant (hissing or whistling) sound
    • n assibilation the development of a consonant phoneme into a sibilant
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Webster's Revised Unabridged Dictionary
    • n Assibilation Change of a non-sibilant letter to a sibilant, as of -tion to -shun duke to ditch.
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Century Dictionary and Cyclopedia
    • n assibilation The act of making sibilant; specifically, in philology, the change of a dental or guttural (or a labial) mute into a sibilant (s, z, sh, zh, ch = tsh, j = dzh), or into a sound approaching that of a sibilant, as for instance a palatal. This change usually results from a tendency to accommodate the mute to an immediately succeeding e, i, or y sound. Thus, t in the Latin natio becomes z (=ts) in the Italian nazione, and is pronounced s in the French nation and sh in the English nation. Similarly, the English t approaches or assumes the sound of ch before the y-sound contained in long u in nature, virtue, etc.
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