Assimilation

Assimilation is a sound change process, when one sound causes another sound to become phonetically more similar to it in some way.

Assimilatory changes can be classified according to the following dichotomies: partial versus total, progressive versus regressive, contact versus distant.

An assimilation is total assimilation if the assimilated sound adopts all the phonetic features of another sound and becomes identical to it: Latin septem 'seven' > Italian sette. An assimilation is partial if the assimilated sound retains at least one of its original phonetic features and adopts only some of the phonetic features of another sound. Thus, Old English efn 'even' > West-Saxon emn.

Regressive (also called anticipatory or right-to-left) assimilation is one in which the sound that undergoes the change (the target) comes earlier in the word than the trigger of assimilation, in other words the change operates backwards: Latin septem 'seven' > Italian sette. In case of progressive (also known as perseveratory or preservative or lag or left-to-right assimilation) assimilation the trigger comes before the target so that the assimilation operates forwards: Proto-Germantic *wulno 'wool' > Old English wull. In rare cases of reciprocal assimilation there is a mutual influence between the two sounds.

In case of contact assimilation (also called immediate assimilation) the sound undergoing assimilation and the one causing it are immediately adjacent: Old English efn 'even' > West-Saxon emn. In case of distant assimilation the two sounds are not adjacent: Proto-Indo-European *penkʷe > Latin kʷinkʷe (spelled quinque). When distant assimilation applies over an entire word it is called harmony (e.g. vowel harmony, nasal harmony).

References

• Campbell, Lyle & Mauricio J. Mixco. 2007. A Glossary of Historical Linguistics. Salt Lake City: University of Utah Press.
• Crowley, Terry. 1997. An introduction to historical linguistics 3rd ed. Auckland: Oxford University Press.
• Kiparsky, Paul. 2003. The phonological basis of sound change. In Handbook of historical linguistics, ed. by Brian D. Joseph and Richard D. Janda, 313–342. Oxford: Basil Blackwell.
• McMahon, April M.S. 1994. Understanding language Change. Cambridge: Cambridge University Press.