Posted: Apr 15, 2012 12:32 pm
by Zwaarddijk
A more detailed list of sound changes, just for reference. This isn't really an "installment", this is more like a badly written appendix.

One thing may be worth noting, though: these don't only happen as historical processes, but any one of them also occurs randomly in speech all the time. When some specific change starts relatively systematically happening in some context, the language is likely to change along that line.

assimilation: the features of one sound change and adopt features of nearby sounds. This is very common in morphophonological contexts, c.f. English leaf - leaves, where historically, f at the end of a word has been less surrounded by voiced sounds, but while the second e still was pronounced, it suddenly was surrounded by voiced sounds on both sides, and thus assimilated the voicing from them. In languages with vowel harmony, one could kind of claim some kind of distant assimilation, whereby e.g. in Finnish, a word such as
katto gets the adessive case ending -lla (katolla), while as kivi gets -llä (kivellä). In fact, in Finnish there's three sets of vowels, {i,e}, {y,ö,ä} and {u,o,a}, the latter two of which force assimilation throughout the word: you find very few words in Finnish that aren't compounds and have vowels from both of those sets (i and e are neutral, although if no sounds are present from the two other sets, the word defaults to the yöä-set). Very similar situations occur in Hungarian, Turkish, Mongolian, and any number of languages around the world. The diachronic origin of this kind of situation is probably very strong vowel assimilation. This sound change tends to be fairly regular.

metathesis: switches the order of sounds. Sometimes for no obvious reason whatsoever, sometimes to make articulation easier. The much maligned "nucular" is a result of metathesis, but so is the form "ask" - which language-historically originally was the now much maligned form "aks". The Biblical Hebrew hitpael-forms undergo regular metathesis if the first consonant of the verb stem are of one certain class, and the last consonant of the prefix goes after:

hitpa'el from pa'al, but hishtamer from shamar - note how we'd expect the form *hitshamer, but the regular metathesis switches them around.
This seems to be a sound change that needn't regularly affect every instance of a sequence of sounds, but in the case of Hebrew given above, it was fairly regular.

dissimilation: the opposite of assimilation. Why we'd change sounds so that two neighbouring sounds have fewer sounds in common isn't obvious - some claim it's to avoid sounding like we're stuttering, there may be reasons to do with increasing the distinctiveness of a word or whatever. But anyways, examples include modern Swedish nyckel from *lyckel, Czech sloboda from proto-slavic *sveboda (avoiding two fricatives in sequence), Spanish nombre from Latin nomine - avoiding a long series of nasal consonants. This is a sound change that generally is not regular.

haplology: the removal of repeated segments. Haplology is an example of exactly that kind of repeated segment, btw, and if it were to undergo haplology, we'd have haplogy instead. England is the result of haplology on "Engla land". This might not necessarily be regular either.

syncope: the loss of some sound inside a word. A good English example is didn't or doesn't, from did not and does not. Another example is lady from hlaf-dige. (although there, other changes as well have occured). This is a fairly regular one.

epenthesis: the introduction of a sound to smooth transition between two sounds or for some other reason. Examples include earlier Spanish nomre > nombre and English linking <r>. Often the sound may have some feature in common with at least one of the sounds, sometimes even with both. Vowels can also be inserted, and in fact early East Slavic inserted vowels to break up every cluster of consonants. English has this morphophonologically present in pretty much every noun whose singular form ends in s - bass - basses; vase, vases; race, races; ... house, houses; ... This is fairly regular.