Nasal place assimilation

Nasal place assimilation, one of the more common phonological processes found in natural languages, occurs when a nasal phoneme assimilates the place features of another consonant in its environment. In the most common cases, an underlyingly coronal nasal assimilates to an immediately following obstruent, yielding a homorganic NO (Nasal + Obstruent) cluster on the surface.

Oftentimes, nasal place assimilation creates nasal allophones that are not orthographically represented because speakers of the language don't hear them as being distinct. In English, for example, the alveolar nasal /n/ takes on the place features of a any following [+consonantal] sound, sonorants as well as obstruents. English speakers will be able to see this by pronouncing the following prepositional phrases and observing what happens with the /n/ of the preposition in when it occurs before different consonants. We know that the nasal consonant of in is /n/ because [n] is its default pronunciation (e.g. when we say the in by itself of before a vowel-initial word, as in ).

(1) English nasal place assimilation

C cluster across word boundary
in + word
in Paris
in France
in the Hague
in Zimbabwe
in Rhode Island
in Chile
in Granada

In the examples in charts (1), (2), and (3) on this page, the phonetic (IPA) transcription for the cluster of interest is given in the leftmost column, and the corresponding cluster in the expression in the next column appears in bolfaced type.

The only nasals distinguished in English orthography, however, are /m/, /n/, and the velar /ŋ/ (usually written ng). Although /n/ in fact corresponds to the set of allphones in cluster initial position in (1), differences between these allophones in assimilation contexts like the one shown tend to remain below the conscious awareness of native speakers who are not used to thinking linguistically.

Interestingly, /n/ does not assimilate to a following glide /w/ or /j/ in English, but remains alveolar in the phrases in Winnipeg and in Yellowstone. As glides are [-consonantal] sounds, the rule for nasal assimilation in English would need to specify [+consonantal] to rule out assimilation in the glide cases.

The alveolar nasal in Catalan also assimilates to the place features of an immediately following consonant, as we see in (2). Unlike English, /n/ in Catalan does assimilate to a following glide (see [ɲʎ] in they are free).

(2) Nasal assimilation with alveolar /n/: ([son] = 'they are')

Target cluster (boldface) English gloss
son amics 'they are friends'
son pocs 'they are few'
son feliços 'they are happy'
son dos 'there are two'
son sincers 'they are sincere'
son rics 'they are rich'
son germans 'they are brothers'
son lliures 'they are free'
son grans 'they are big'

In general, the bilabial nasal in Catalan does not assimilate to a following consonant. In particular, the forms in (4a) show that labial nasals do not assimilate to a following coronal or velar consonant. However, there is a systematic exception: the examples in (4b) show that the labial nasal /m/ does agree with the place features of a following labial consonant, whether it be bilabial or labio-dental.

(3) Nasal assimilation with bilabial /m/: ([som] = 'we are')

a. No /m/ assimilation with non-labials.

Target cluster (boldface) English gloss
som amics 'we are friends'
som dos 'we are two'
som sincers 'we are sincere'
som rics 'we are rich'
som germans 'we are brothers'
som lliures 'we are free'
som grans 'we are big'

b. /m/ agrees with the place of another labial.

Target cluster (boldface) English gloss
som pocs 'we are few'
som feliços 'we are happy'

Based on the Catalan data in (2) and (3), we can write the rule in (4a) to account for /n/ assimilation. (Note that since /n/ assimilates to both true consonants and glides we cannot refer to a specific value for the feature [consonantal] in (4a), and must instead rely on [-syllabic]). Because the labial nasal behaves differently from the alveolar nasal, we will write the separate rule in (4b) to account for /m/ assimilation.

(4) Catalan Nasal Place Assimilation

a. /[+nasal, +coronal, +anterior]/ → [αplace] / ___ [-syllabic, αplace]
'Alveolar /n/ acquires the full set of place features of any nonsyllabic segment that follows it.'
b. /[+nasal, +labial]/ → [αplace] / ___ [-syllabic, +labial, αplace]
'Labial /m/ acquires the full set of place features of any nonsyllabic labial that follows it.'

(Note: one way in which to distinguish between bilabial and labiodental place is to use the feature [distributed], with bilabials having [+distributed] and labiodentals [-distributed].)

In the next section, we describe the effects of a rule that interacts with place assimilation in Central Catalan, Cluster Simplification.

prev | top | next