Compensatory lengthening

Sound change and alternation
Metathesis Quantitative metathesis
Lenition Consonant gradation Consonant voicing and devoicing Assibilation L-vocalization Debuccalization
Fortition
Epenthesis Anaptyxis Excrescence Prosthesis Paragoge Unpacking Vowel breaking
Elision Apheresis Syncope Apocope Haplology Fusion Cluster reduction
Cheshirization Compensatory lengthening Nasalization Tonogenesis Floating tone
Assimilation Coalescence Coarticulation Palatalization Velarization Labialization Final devoicing Metaphony (vowel harmony, umlaut) Consonant harmony
Dissimilation
Sandhi Liaison, linking R Consonant mutation Tone sandhi Hiatus Synalepha  Elision Crasis Synaeresis and diaeresis Synizesis
Other types Rhotacism Rhinoglottophilia Sulcalization
view

Compensatory lengthening in phonology and historical linguistics is the lengthening of a vowel sound that happens upon the loss of a following consonant, usually in the syllable coda. This may be considered an extreme form of fusion (Crowley 1997:46), or possibly arise from speakers' attempts to preserve a word's moraic count.^[1]

An example from the history of English is the lengthening of vowels that happened when the voiceless velar fricative /x/ and its palatal allophone [ç]^[2] were lost from the language. For example, in Chaucer's time the word night was phonemically /nixt/; later the /x/ was lost, but the /i/ was lengthened to /iː/ to compensate. (Later the /iː/ became /aɪ/ by the Great Vowel Shift.)

Both the Germanic spirant law and the Ingvaeonic nasal spirant law show vowel lengthening compensating for the loss of a nasal.

Non-rhotic forms of English have a lengthened vowel before a historical post-vocalic */r/: in Scottish English, girl has a short /i/ followed by a light alveolar /r/, as presumably it did in Middle English; in Southern British English, the */r/ has dropped out of the spoken form and the vowel has become a "long schwa".

Greek

Compensatory lengthening is very common in Greek. It is particularly notable in forms where n or nt comes together with s, y (= ι̯), or i. The development of nt + y was perhaps thus:

• *mont-yă → montsa (palatalization ty → ts) → mõtsa (nasalization and vowel lengthening) → mõssa → mõsa (shortening ss → s) → mōsa (denasalization, retention of long vowel) = μοῦσα "muse"

Forms with this type of compensatory lengthening include the nominative singular and dative plural of many participles, adjectives, and nouns, the 3rd person plural ending for present and future active of all verbs, and the 3rd person singular present of athematic verbs:

• *πάντ-ς → πᾶς "every, whole" (masculine nominative singular)^[3]
• *πάντ-ι̯ᾰ → *πάντσα → πᾶσα (feminine)
• *πάντ-σι → πᾶσι (masculine/neuter dative plural)
• compare παντ-ός (m./n. genitive singular)

• *όντ-ι̯ᾰ → *όντσα → οὖσα participle "being" (feminine nominative singular)^[4]
• *οντ-ίᾱ → *ονσία → οὐσία "property, essence"
• compare ὀντ-ός (m./n. genitive singular, from participle ὤν "being",)

• Doric ἄγ-ο-ντι → ἄγοντσι → Attic/Ionic ἄγουσι "they drive"

• Doric τί-θε-ντι → *τίθεντσι → Attic/Ionic τίθεισι "he/she places"^[5]

See also

• Mora
• Phonological history of the English language
• Ancient Greek nouns

References

• Crowley, Terry. (1997) An Introduction to Historical Linguistics. 3rd edition. Oxford University Press.
• Smyth, Greek Grammar on CCEL.

1. ^ Hayes, Bruce (1989). "Compensatory Lengthening in Moraic Phonology". Linguistic Inquiry (The Massachusetts Institute of Technology) 20 (2): 253–306. 
2. ^ Millward, C. M. (1996). A Biography of the English Language. Boston: Wadsworth. p. 84. 
3. ^ Smyth, par. 299: adjs. in nt.
4. ^ Smyth, par. 301 a and d: participles in nt.
5. ^ Smyth, par. 462 note: Doric athematic verb endings.