When we speak, we often change the ways we pronounce words. This tends to happen a lot if we speak fast. But do you know why this happens? This relates to the topic we are focusing on today - phonetic assimilation.
We will explore the definition of phonetic assimilation, the different types, and some examples of each. We will also consider the differences between assimilation, elision, and epenthesis - as it is easy to get these three processes mixed up!
Fig. 1 - Assimilation occurs in our speech when we slightly change the way we pronounce words.
Assimilation in phonetics
Assimilation in phonetics is the process in which a sound is influenced by and becomes similar to a surrounding sound. This means that the pronunciation can vary depending on the order of certain letters in different words. This is usually done to ease pronunciation, especially when words are said quickly.
An example would be the word ‘handbag’. Native speakers rarely pronounce each letter clearly as this does not flow well and is more difficult to pronounce in fast speech. Instead, they would probably pronounce it as /hæmbæg/ (hambag).
Why is this?
This happens because both the /d/ and /b/ sounds have different places of articulation, meaning they are pronounced using different parts of the mouth:
The /n/ sound is also pronounced by tapping the tongue against the alveolar ridge, but, because it comes before the bilabial consonant /b/, it is labialised instead. This means that the /n/ sound turns into an /m/ sound. This makes it easier to pronounce the /m/ and /b/ sequentially, as they are both pronounced using the same parts of the mouth (the lips).
Other examples of words where this process occurs are sandbox, standby, windbreaker, sandwich etc.
The simplifying of consonants for ease of pronunciation can be called cluster reduction.
What are the assimilation phonetics rules?
Assimilation in phonetics can be described as having a certain set of rules. These rules determine how sounds assimilate to others depending on what's surrounding them. For example a sound being changed because of what precedes it such as the 's' in 'bags' being changed to a voiced 'z' sound. These assimilation 'rules' determine the different types of assimilation in phonetics. We'll have a look at these now.
Types of assimilation in phonetics
There are different types of assimilation depending on which sounds are altered. A sound can either be influenced by the sound that comes before it or after it. The types are as follows:
- Progressive (before)
- Regressive (after)
Let's look at these in more detail.
Progressive assimilation
This refers to when a sound is influenced by the sound that comes before it.
The /s/ sound is influenced by the previous sound and changes to a /z/ sound, e.g.
/bægs/ (bags) → /bægz/ (bagz)
Regressive assimilation
This refers to when a sound is influenced by the sound that comes after it.
The /n/ sound is influenced by the following sound and changes to an /m/ sound, e.g.
/ɪnfəmeɪʃən/ (information) → /ɪmfəmeɪʃən/ (imformation).
What are the degrees of assimilation?
The types of phonetic assimilation mentioned above can further be split into two degrees of assimilation: total and partial.
Total assimilation
This refers to when the sound affected by the assimilation becomes the same as the sound that causes the assimilation. You can notice this within words or across sentences.
For example, let's take the phrase 'this shoe'. In fast speech, the /s/ sound at the end of 'this' is affected by the /ʃ/ (sh sound) at the beginning of 'shoe' and changes to the /ʃ/ sound.
/ðɪs ʃuː/ (this shoe) → /ðɪʃʃuː/ (thish-shoe)
Partial assimilation
This refers to when the sound affected by the assimilation becomes similar to the sound that causes the assimilation but does not change completely.
For example, let's take the phrase 'sit back'. In fast speech, the /t/ sound is influenced by the following /b/ sound and changes to become a /p/ sound:
/sɪt bæk/ (sit back) → /sɪpbæk/ (sip-back)
/p/ is similar to a /b/ as they share the same place of articulation - both sounds are made by placing your lips together and pushing air out. But, they are not entirely the same, so this is only partial assimilation.
Partial assimilation is more common than total!
Phonetic assimilation examples
Below are some examples of phonetic assimilation:
| Change | Examples | Type of assimilation |
| /n/ changes to an /m/ | /ɪn pærɪs/ (in Paris) → /ɪm pærɪs/ (im Paris)/sʌnbed/ (sunbed) → /sʌmbed/ (sum-bed) | Regressive |
| /d/ changes to a /t/ | /mæʃd/ (mashed) → /mæʃt/ (masht)/wɒʃd/ (washed) → /wɒʃt/ (washt) | Progressive |
| /n/ changes to an /ŋ/ | /bænk/ (bank) → /bæŋk/ (bangk)/ɪnkərekt/ (incorrect) → ɪŋkərekt (ingcorrect) | Regressive |
| /s/ changes to a /z/ | /dɒgs/ (dogs) → /dɒgz/ (dogz)/rʌgs/ (rugs) → /rʌgz/ (rugz) | Progressive |
| /v/ changes to an /f/ | /hæv tu:/ (have to) → /hæf tu:/ (haf to)/faɪvpens/ (five pence) → /faɪf pens/ (faif pence) | Regressive |
Assimilation and elision in phonetics
It is easy to mix up elision and assimilation as they often occur simultaneously, and both are processes that change the pronunciation of words.
Elision refers to when consonants are omitted from a word/phrase. This is usually done to make words or phrases easier to pronounce in fast speech. It helps the utterance flow more naturally.
In the phrase ‘you and me’, instead of pronouncing all the letters, the /d/ sound can be dropped, and the /æ/ can be replaced with a schwa /ə/ sound. The schwa sound is not as strong of a sound and makes the words flow more efficiently.
So, /juː ænd miː/ (you and me) turns into /juː ən miː/ (you ‘n me).
Epenthesis vs. assimilation in phonetics
This refers to when extra sounds are added to a word. This does not change the spelling of the word, only the pronunciation.
The word ‘hamster’ may be pronounced as /hæmpstə/ (hampster), as it is easier to transition from a /p/ to an /s/ than to follow an /m/ with an /s/due to the places of articulation.
The use of the rhotic /r/ sound in words that do not contain it in the spelling. This is known as the intrusive r.
This is commonly found in most varieties of British English, where /r/ is added to words that usually would not contain one.
E.g. The word drawing is pronounced like /drɔːɪŋ/ (draw-ring).
Assimilation and accommodation in phonetics
The terms assimilation and accommodation are both often used in phonetics when we talk about sound change. These are not interchangeable terms though; they relate to different types of sound change.
Assimilation is when a sound change is influenced by and becomes similar to its surrounding speech sounds.
Accommodation is when people's speech sounds change depending on who they're talking to. For example, if you're trying to make someone feel more comfortable or gain social approval, you'll slightly alter how you speak to accommodate the speech of your interlocutor. You can also create distance from the other person by emphasising linguistic differences and speaking differently to them.
Both assimilation and accommodation are most often subconscious sound changes.
Phonetic Assimilation - Key Takeaways
- Phonetic assimilation is the process in which a sound is influenced by and becomes similar to a surrounding sound.
- There two types of phonetic assimilation are: progressive and regressive.
- The two degrees of phonetic assimilation are: total and partial.
- Elision refers to when consonants are omitted from a word/phrase.
- Epenthesis refers to when extra sounds are added to a word.
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