How is phonology studied?

Every language has an organised sound system. Phonology is concerned with processes in the mind, determining the rules of a language and how we organise, study and form sounds in speech.


We each have tacit knowledge* of our native language. This tacit knowledge allows us to adhere to the rules of the relevant sound system.

*Tacit Knowledge = When you know something without understanding how or why you came to ‘know it’.

For example: if you were asked to make up a word you would be more likely to say something like “plond” rather than “plofw”. This is because the underlying knowledge you have of the English language tells you that two consonants such as ‘fw’ cannot appear next to each other at the end of a word.

Identifying Phonemes


Phonemes are the smallest sound units of language that bear meaning. Phonemes are contrastive, which means that they are meaningfully different. Phonemes are said to be in contrastive distribution, that is they occur in the same environment and cause a change in meaning. An example of two words that differ only in one phoneme is the words ‘pat’ and ‘mat, the substitution of ‘p’ for ‘m’ creates two different words that mean different things; this is a called a minimal pair. To be a minimal pair, the words must only differ in one phoneme occurring in the same place within the words. Minimal pairs are a test for phoneme status, so from this example because the substitution of ‘p’ for ‘m’ creates different words that differ in meaning, they are different phonemes. The phoneme changed could be a consonant or a vowel and can occur at any place in the word. You can also get minimal sets, where there are three, or more, words that differ by only one phoneme for example ‘bit’, ‘bot’, ‘bet’, ‘boot’ and ‘beat’ are part of a minimal set.  Phonemes are written in slashes, for example /p/ and /m/, this notation shows the sounds as being underlying representations, which is the form of the sound that is stored in our minds.


As slashes are used to represent the underlying representations, we need a way of showing what sounds are actually produced, the surface forms. This is done through the use of square brackets [ ]. Allophones are different realisations of a phoneme depending on where in the word it occurs. To be allophones of a phoneme the sounds must be in complementary distribution, which means that they occur in different environments within words. Allophones are phonetically similar to each other because they are different versions of the same sound.

One example of allophones are the different productions of the phoneme /t/. This phoneme can be realised differently in different environments. Word initially, /t/ is produced as [tʰ] which symbolises that the sound has been produced with aspiration, and when /t/ appears after ‘s’ it is produced as [t]. You can see this difference for yourself – put your hand to your mouth and produce the word ‘stop’ and then ‘top’, when you produce ‘top’ you should feel a puff of air that does not occur with ‘stop’. For more information on aspiration, and how it is produced, see the phonetics section. Additionally, /t/ can also be produced differently according to dialect, many dialects of English have a glottal stop [ʔ] in the middle of words, for example words such as ‘butter’ can be produced with either [t] or [ʔ]. In American dialect, a tap/flap is produced [ɾ] which gives a production that resembles ‘budder’.  Although these are different sounds, as native speakers of a language we would categorise all of the allophones as being a single sound, the phoneme /t/.     

Another example that is found in English is /l/ being produced as a ‘clear’ [l] or a ‘dark’ [ɫ]. Which realisation occurs is a result of allophonic rules. They never occur in the same place in the word, [l] is always at the start of the word, and [ɫ] is always at the end of the word. They are also phonetically similar, they are both lateral approximants, therefore, they are allophones of a single phoneme /l/. You can tell a difference between the first and second ‘l’s in words such as ‘little’ and ‘ladle’.

Minimal pair test (also known as contrastive pairs)

  • A phoneme is defined as a single meaningful unit.
  • ‘bat’ and ‘bats’ have two different meaning; this is due to one phoneme being different – /s/ 
  • So, we can clarify that /s/ is a phoneme as when added on the end of the word it changes to meaning from a singular noun to a plural noun.
  • Other examples are ‘lack’ & ‘wack’, ‘seat’ & ‘beat’, ‘cry’ & ‘dry’ – as long as the phoneme changes the words meaning semantically or grammatically it is classed as a phoneme.

Phoneme Sequences – Syllable structures

syllable is a unit of phonological organisation which is larger than the sound segment (phoneme) and smaller than the word.  In the middle of the syllable there is usually a vowel, and then consonants arrange themselves around the vowel.

Just like our brains have abstract rules that determine how sounds are combined, there is an abstract process called syllabification which organises sound segments into syllables.

Multi-tiered phonological theory

This is how syllables are structured.

The formal names for the parts of a syllable are the onset and the rhyme, which contains the nucleus and the coda.  The symbol to signify a syllable is ‘σ’, and a full word, ‘W’.

The nucleus is the central and compulsory component of the syllable and is usually a vowel.  However, the nucleus can also be a consonant – this is called a syllabic consonant and in English this can occur with /l/ and /n/ in words such as ‘saddle’ and ‘button’, which would be produced like [s] ‘sadl’ and [b] ‘butn’ respectively. The nucleus can be non-branching (a short vowel) or branching (a monophthong or diphthong – see phonetics).

The coda is any consonant which follows the nucleus and is the closing part of the syllable.  Codas can be absent, such as in “pea”, non-branching (1 consonant), as in “pin” or branching (more than one consonant) as in “drink”. If a syllable does not have a coda, it is called an open syllable. A syllable with a coda is a closed syllable.

The rhyme consists of the nucleus and coda. 

The onset is any consonant which precedes the nucleus within the same syllable.  Like codas, onsets can also be absent, non-branching or branching.

Phonological Processes


  • Assimilation is when one phoneme is pronounced in a way which is similar to a nearby phoneme, and this can affect the place of articulation, manner of articulation and voicing.  There are two types of assimilation: progressive and regressive.
    • Progressive assimilation is when a phoneme affects the realisation of a following phoneme.  For example, “it is” can be realised as “it’s”: /ɪt ɪz/ > [ɪts] where the voiced alveolar fricative /z/ becomes voiceless [s].
    • Regressive assimilation is when a phoneme affects the realisation of a preceding phoneme.  For example, “hot coffee” can be realised as [hɒkkɒfi:] (“hoccoffee”), where the voiceless alveolar plosive /t/ has undergone a voice assimilation to become voiced and undergone a place assimilation to become velar, like the voiced velar plosive /k/.


  • Dissimilation is the opposite of assimilation and occurs where a sound is becoming less similar to another sound. For example, in Latin the word [arbor] meaning ‘tree’ changing into [arbol] in Spanish to avoid the two ‘r’ sounds being in close contact.  


  • Coalescence is when two contiguous consonantal phonemes are replaced by a single phoneme which shares features of the two original ones.  A common place this can occur is with affricates, for example “bet you” can be realised as [bɛʧu:] (“bechoo”).


  • Elision is when a sound is deleted in a sequence, and this is a strategy often used to remove unstressed vowels or avoid complex consonantal clusters, for example “police” has undergone vowel deletion to be realised as [pʰli:s] (“pleece”).


  • Liaison occurs when a sound is inserted between two words for easier articulation.  This usually happens when word 1 ends with a vowel and word 2 begins with a vowel, for example with “idea of” > “idea-r-of” [aɪdi:əɹɒv].


  • Epenthesis is inserting an extra sound into the middle of a word, for example in “hamster” > [hampstə] (hampster) or “agency” > [ɛɪʤntsi:] (agentsy).

Lenition (Weakening)

  • Lenition (weakening) is when a sound becomes weaker on the strength scale:

Plosive > Fricative > Approximant > Vowel > zero

Aspirated > voiceless > voiced

A voiceless aspirated plosive is the strongest category on the scale as it differs the most from the qualities of a vowel whereas voiced approximants are weaker due to being more similar. For example, in Spanish, /d/ becomes [ð] between two vowels, showing the transition from plosives to the weaker category of fricatives.

Fortition (Strengthening)

  • Fortition (strengthening) is the opposite of lenition and occurs when a sound becomes stronger on the manner of articulation scale. For example, in German, when the voiced alveolar plosive /d/ is word finally it comes devoiced to [t], showing a movement up in the scale from voiced to voiceless. This seen in the transition from [ʁɑːdəs] meaning ‘of wheel’ to [ʁɑːt] meaning ‘wheel’.

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