Lenition


In linguistics, lenition is a sound change that alters consonants, making them more sonorous. The word lenition itself means "softening" or "weakening". Lenition can happen both synchronically and diachronically. Lenition can involve such changes as voicing a voiceless consonant, causing a consonant to relax occlusion, to lose its place of articulation, or even causing a consonant to disappear entirely.
An example of synchronic lenition in American English is found in flapping in some dialects: the of a word like wait becomes the more sonorous in the related form waiting. Some dialects of Spanish show debuccalization of to at the end of a syllable, so that a word like estamos "we are" is pronounced. An example of diachronic lenition can be found in the Romance languages, where the of Latin patrem becomes in Italian padre and in Spanish padre, while in Catalan pare, French père and Portuguese pai it has disappeared completely. Along with assimilation, lenition is one of the primary sources of phonological change of languages.
In some languages, lenition has been grammaticalized into a consonant mutation, which means it is no longer triggered by its phonological environment but is now governed by its syntactic or morphological environment. For example, in Welsh, the word cath "cat" begins with the sound, but after the definite article y, the changes to : "the cat" in Welsh is y gath. This was historically due to intervocalic lenition, but in the plural, lenition does not happen, so "the cats" is y cathod, not *y gathod. The change of to in y gath is thus caused by the syntax of the phrase, not by the phonological position of the consonant.
The opposite of lenition, fortition, a sound change that makes a consonant "stronger", is less common.

Types

Lenition involves changes in manner of articulation, sometimes accompanied by small changes in place of articulation. There are two main lenition pathways: opening and sonorization. In both cases, a stronger sound becomes a weaker one. Lenition can be seen as a movement on the sonority hierarchy from less sonorous to more sonorous, or on a strength hierarchy from stronger to weaker.
In examples below, a greater-than sign indicates that one sound changes to another. The notation > means that changes to.
The sound change of palatalization sometimes involves lenition.
Lenition includes the loss of a feature, such as deglottalization, in which glottalization or ejective articulation is lost: or >.
The tables below show common sound changes involved in lenition. In some cases, lenition may skip one of the sound changes. The change voiceless stop > fricative is more common than the series of changes voiceless stop > affricate > fricative.

Opening

In the opening type of lenition, the articulation becomes more open with each step. Opening lenition involves several sound changes: shortening of double consonants, affrication of stops, spirantization of stops or affricates, debuccalization, and finally elision.
geminated stop→stop→affricate→fricative→placeless approximant→no sound
original sound→degemination→affrication→spirantization
→debuccalization→elision
→→→→→
→→→→→
→→→→→
→→→→→
→→→→→

Sonorization

The sonorization type involves voicing. Sonorizing lenition involves several sound changes: voicing, approximation, and vocalization.
Sonorizing lenition occurs especially often intervocalically. In this position, lenition can be seen as a type of assimilation of the consonant to the surrounding vowels, in which features of the consonant that are not present in the surrounding vowels are gradually eliminated.
Some of the sounds generated by lenition are often subsequently "normalized" into related but cross-linguistically more common sounds. An example would be the changes → → and → →. Such normalizations correspond to diagonal movements down and to the right in the above table. In other cases, sounds are lenited and normalized at the same time; examples would be direct changes → or →.

Vocalization

is a subtype of the sonorization type of lenition. It has two possible results: a velar approximant or back vowel, or a palatal approximant or front vowel. In French, l-vocalization of the sequence resulted in the diphthong, which was monophthongized, yielding the monophthong in Modern French.
lateral approximant→semivowel→vowel
→
→
→→

Mixed

Sometimes a particular example of lenition mixes the opening and sonorization pathways. For example, may spirantize or open to, then voice or sonorize to.
Lenition can be seen in Canadian and American English, where and soften to a tap when not in initial position and followed by an unstressed vowel. For example, both rate and raid plus the suffix -er are pronounced. In many British English dialects, a different lenition that affects only takes place: > . The Italian of Central and Southern Italy has a number of lenitions, the most widespread of which is the deaffrication of to between vowels: post-pausal cena 'dinner' but post-vocalic la cena 'the dinner'; the name Luciano, although structurally, is normally pronounced. In Tuscany, likewise is realized between vowels, and in typical speech of Central Tuscany, the voiceless stops in the same position are pronounced respectively, as in → 'the house', → 'hole'.

Effects

Diachronic

lenition is found, for example, in the change from Latin into Spanish, in which the voiceless stops first changed into their voiced counterparts, and later into the approximants or fricatives : vita > vida, lupa > loba, caeca > ciega, apotheca > bodega. One stage in these changes goes beyond phonetic to have become a phonological restructuring, e.g. > . The subsequent further weakening of the series to phonetic, as in is diachronic in the sense that the developments took place over time and displaced as the normal pronunciations between vowels. It is also synchronic in an analysis of as allophonic realizations of : illustrating with, 'wine' is pronounced after pause, but with intervocalically, as in 'of wine'; likewise, →.
A similar development occurred in the Celtic languages, where non-geminate intervocalic consonants were converted into their corresponding weaker counterparts through lenition, and voiceless stops became voiced. For example, Indo-European intervocalic * in * "people" resulted in Proto-Celtic, Primitive Irish *tōθā, Old Irish and ultimately debuccalisation in most Irish and some Scottish dialects to, shift in Central Southern Irish to, and complete deletion in some Modern Irish and most Modern Scots Gaelic dialects, thus.
An example of historical lenition in the Germanic languages is evidenced by Latin-English cognates such as pater, tenuis, cornu vs. father, thin, horn. The Latin words preserved the original stops, which became fricatives in old Germanic by Grimm's law. A few centuries later, the High German consonant shift led to a second series of lenitions in Old High German, chiefly of post-vocalic stops, as evidenced in the English-German cognates ripe, water, make vs. reif, Wasser, machen.
Although actually a much more profound change encompassing syllable restructuring, simplification of geminate consonants as in the passage from Latin to Spanish such as CUPPA > 'cup' is often viewed as a type of lenition.

Synchronic

Allophonic

All varieties of Sardinian, with the sole exception of Nuorese, offer an example of sandhi in which the rule of intervocalic lenition applying to the voiced series /b d g/ extends across word boundaries. Since it is a fully active synchronic rule, lenition is not normally indicated in the standard orthographies.
A series of synchronic lenitions involving opening, or loss of occlusion, rather than voicing is instead found for post-vocalic in many Tuscan dialects of Central Italy. Stereotypical Florentine, for example, has the of as casa 'house' in a post-pause realization, in casa 'in house' post-consonant, but la casa 'the house' intervocalically. Word-internally, the normal realization is also : buco 'hole' →.

Grammatical

In the Celtic languages, the phenomenon of intervocalic lenition historically extended across word boundaries. This explains the rise of grammaticalised initial consonant mutations in modern Celtic languages through the loss of endings. A Scottish Gaelic example would be the lack of lenition in am fear and lenition in a’ bhean . The following examples show the development of a phrase consisting of a definite article plus a masculine noun compared with a feminine noun taking the ending -a. The historic development of lenition in those two cases can be reconstructed as follows:
Synchronic lenition in Scottish Gaelic affects almost all consonants. Changes such as to involve the loss of secondary articulation; in addition, → involves the reduction of a trill to a tap. The spirantization of Gaelic nasal to is unusual among forms of lenition, but it is triggered by the same environment as more prototypical lenition..
Spirantization
Loss of secondary articulation
Debuccalization
Elision
Reduction of place markedness

Blocked lenition

Some languages which have lenition have in addition complex rules affecting situations where lenition might be expected to occur but does not, often those involving homorganic consonants. In Scottish Gaelic, for example, there are three homorganic groups:
In a position where lenition is expected due to the grammatical environment, lenition tends to be blocked if there are two adjacent homorganic consonants across the word boundary. For example:
In modern Scottish Gaelic this rule is only productive in the case of dentals but not the other two groups for the vast majority of speakers. It also does not affect all environments any more. For example, while aon still invokes the rules of blocked lenition, a noun followed by an adjective generally no longer does so. Hence:
There is a significant number of frozen forms involving the other two groups and environments as well, especially in surnames and place names:
Though rare, in some instances the rules of blocked lenition can be invoked by lost historical consonants, for example, in the case of the past-tense copula bu, which in Common Celtic had a final -t. In terms of blocked lenition, it continues to behave as a dental-final particle invoking blocked lenition rules:
Blocked lenition phenomena are also known to occur in Irish and Spanish.

Orthography

In the modern Celtic languages, lenition of the "fricating" type is usually denoted by adding an h to the lenited letter. In Welsh, for example, c, p, and t change into ch, ph, th as a result of the so-called "aspirate mutation". An exception is Manx orthography, which tends to be more phonetic, although in some cases etymological principles are applied. In the Gaelic script, fricating lenition is indicated by a dot above the affected consonant, while in the Roman script, the convention is to suffix the letter h to the consonant, to signify that it is lenited. Thus, a ṁáṫair is equivalent to a mháthair. In Middle Irish manuscripts, lenition of s and f was indicated by the dot above, while lenition of p, t, and c was indicated by the postposed h; lenition of other letters was not indicated consistently in the orthography.
Voicing lenition is represented by a simple letter switch in the Brythonic languages, for instance carreg, "stone" → y garreg, "the stone" in Welsh. In Irish orthography, it is shown by writing the "weak" consonant alongside the "strong" one: peann, "pen" → ár bpeann "our pen", ceann, "head" → ár gceann "our head".
Although nasalization as a feature also occurs in most Scottish Gaelic dialects, it is not shown in the orthography on the whole as it is synchronic, rather than the diachronic Irish type sonorization. For example taigh "house" → an taigh "the house".

Consonant gradation

The phenomenon of consonant gradation in Finnic languages is also a form of lenition.
An example with geminate consonants comes from Finnish, where geminates become simple consonants while retaining voicing or voicelessness. It is also possible for entire consonant clusters to undergo lenition, as in Votic, where voiceless clusters become voiced, e.g. itke- "to cry" → idgön.
If a language has no obstruents other than voiceless stops, other sounds are encountered, as in Finnish, where the lenited grade is represented by chronemes, approximants, taps or even trills. For example, Finnish used to have a complete set of spirantization reflexes for, though these have been lost in favour of similar-sounding phonemes. In Pohjanmaa Finnish, was changed into, thus the dialect has a synchronic lenition of an alveolar stop into an alveolar trill. Furthermore, the same phoneme undergoes assibilation → before the vowel, e.g. root vete- "water" → vesi and vere-. Here, vete- is the stem, vesi is its nominative, and vere- is the same stem under consonant gradation.

Fortition

Fortition is the opposite of lenition: a consonant mutation in which a consonant changes from one considered weak to one considered strong. Fortition is less frequent than lenition in the languages of the world, but word-initial and word-final fortition is fairly frequent.
Italian, for example, presents numerous regular examples of word-initial fortition both historically and synchronically.
Catalan is among numerous Romance languages with diachronic word-final devoicing (frigidus > > fred. Fortition also occurs in Catalan for in consonant clusters with a lateral consonant (Lat. populus > poble or.
Word-medially, is subject to fortition in numerous Romance languages, ranging from in many speech types on Italian soil to in some varieties of Spanish.

General references