phonology

In linguistics, the study of the sound systems of languages. Its main activity is the discovery of the distinctive sounds, or phonemes, of the language.

A person who is phonologically aware can create rhymes and use alliteration. People with speaking and reading difficulties can have problems with the blending of component sounds.

The precise definition of a phoneme has caused much difficulty, but a working definition is that phonemes are the distinctive phonic elements of a language. There are several varieties of t in English (phonetically, there are different varieties of t in the words ‘top’, ‘stop’, ‘tree’, ‘bottle’, ‘alter’, ‘lightning’, and ‘antler’). They are, however, of no distinctive value within the system of the language: it is impossible in English to have a pair of words differentiated solely by the distinction between two of these varieties of t. The distinction between the variants is determined solely by phonetic context. Variants that do not change meaning in a given language are called allophones. These variants are therefore not distinct phonemes, but allophones of the phoneme /t/. On the other hand, /d/ and /t/ are phonemes in English, because such pairs of words as ‘din’ and ‘tin’, ‘ridden’ and ‘written’, ‘bad’ and ‘bat’, are distinguished solely by the difference between these two sounds.

Sounds that are allophones in one language may be phonemes in another; for example, sounds similar to the English phonemes that distinguish between the words ‘den’ and ‘then’ also exist in Spanish, but in that language they are allophones, the choice between them being governed by phonetic circumstances.