Sound change notation

Alternative title: List of sound changes.

Sound change is what happens when a people's pronunciation shifts over time. Languages are living systems, and their sounds slowly drift, sometimes so gradually that speakers barely notice it happening. (This is not to say that sound change is the only element of language evolution.)

To describe these sound changes, linguists use sound change notation. The most common form of notation being "SPE" notation, popularised in The Sound Pattern of English (Chomsky & Halle, 1968). "SPE" notation is so common that it is simply called sound change, and is what this article will be about. There are some drawbacks to "SPE" notation that competing "non-linear" frameworks can be better at solving -- I will mention these drawbacks and these other frameworks at the end of the article.

In its most basic form, one sound transforms into another in a "rule". For example:

This means that sound A has become sound B.

Multiple changes in one rule

Two or more sounds transforming, or rather merging, into another. For example both A and B were to transform into C may be written like this:

A series of changes can be written like this:

This means A becomes C; B becomes D; and C becomes E, with an implication that these occur at the same time.

If there are multiple arrows in a rule, it can be interpreted in two ways depending on the author's intentions. For example:

This can either be A becomes B then C. Essentially A has a medial form B before becoming C, a "series of changes".

Or if the author describes it as a "chain shift": B transforms to C while A transforms to B.

The environment

Up to this point, the rules have applied in all contexts. If the rule only applies when it meets certain conditions, the following notation is used:

This means Sound A becomes sound B after C and before D. The underscore is used to represent the sound being changed.

If the rule always applies except when it meets an environment, use a ! instead of a / like so:

Unfortunately the exclamation mark is also used as the IPA phoneme [!].

Special boundaries

To represent not a sound but a word boundary, a hash / number-sign / pound symbol # is used in the environment:

This means A becomes B only when A is at the beginning of the word.

And this means A becomes B only when A is at the end of the word.

The Greek letter lowercase sigma σ is used to indicate a syllable. To represent a syllable boundary, a closing square bracket followed by a subscript sigma can be used.

Other conventions may have a dollar sign $ as marking a syllable boundary.

The first example means that the sound change takes place only at the end of a syllable.

Brackets

In certain cases, there might be optional properties to a rule. in these cases they are enclosed in round brackets (parenthesis):

This means that A becomes B before D, whether or not C is in the way.

If more than one sound is affected or more than one environment intervenes, then curly brackets (braces) are used.

This means that the change takes place before C or word-finally.

Deletion and epenthesis

The empty set symbol ∅ is used to represent deletion or epenthesis depending on its location. Unfortunately it looks a lot like the IPA vowel [ø].

This is how deletion is written:

This means A is deleted before C.

Epenthesis is a fancy word for insertion that linguists use:

This means A is inserted before a C.