Assibilation

In linguistics, assibilation is a sound change resulting in a sibilant consonant. It is a form of spirantization and is commonly the final phase of palatalization.

The word "assibilation" itself contains an example of the phenomenon, as it is pronounced /əsɪbɪleɪʃən/. The Classical Latin tio was pronounced /tio/ (for example, assibilatio was pronounced /asːibilatio/ and attentio /atːentio/). However, in Vulgar Latin, it assibilated to /tsio/, which can still be seen in Italian: attenzione.

In French, lenition then gave /sj/, which was further palatalized in the English loanword to /ʃ/.

In the High German consonant shift, voiceless stops /p, t, k/ spirantized to /f, s, x/ at the end of a syllable. The shift of /t/ to /s/ (as in English water, German Wasser) is assibilation.

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