Scottish vowel length rule


The Scottish vowel length rule, also known as Aitken's law, describes how vowel length in Scots, Scottish English, and, to some extent, Ulster English and Geordie is conditioned by the phonetic environment of the vowel. Primarily, the rule is that certain vowels are phonetically long in the following environments:
Exceptions can also exist for particular vowel phonemes, dialects, words, etc., some of which are discussed in greater detail below.

Phonemes

The underlying phonemes of the Scottish vowel system are as follows:
★ = Vowels that definitively follow the Scottish vowel length rule.

Rule specifics and exceptions

The Scottish vowel length rule affects all vowels except the always-short vowels 15 and 19 and, in many Modern Scots varieties, the always-long Scots-only vowels 8, 11, and 12 that do not occur as phonemes separate from in Scottish Standard English. The further north a Scots dialect is from central Scotland, the more it will contain specific words that do not adhere to the rule.
  • Vowel 8a, which only occurs stem-finally, and vowel 10 are always short; therefore, vowel 1 in its short form, vowel 8a, and vowel 10 all merge as the diphthong. In its long form, the quality of vowel 1 changes, so it is here transcribed as to reflect that.
  • and are usually short in all environments.
  • In some Modern Scots varieties may merge with in long environments. In Scots dialects|Ulster Scots], and are usually always long and the realisation of is short before a voiceless consonant or before a sonorant followed by a voiceless consonant but long elsewhere.
  • ,,,,,, and, are usually long in the following environments and short elsewhere:
  • * In stressed syllables before voiced fricatives, namely, and also before. So in Scottish English, for example, save, doze, teethe and confusion have longer vowels than safe, dose, teeth and Confucian .
  • ** In some Modern Scots varieties, also before the monomorphemic end-stresses syllables, + any voiced consonant, and.
  • ** In Shetland dialect the realisation of underlying, usual in other Scots varieties, remains a long environment.
  • * Before another vowel
  • * Before a morpheme boundary, so for example stayed is pronounced with a longer vowel than staid.
  • usually occurs in all phonetic environments in final stressed syllables.

History

The Scottish vowel length rule is assumed to have come into being between the early Middle Scots and late Middle Scots periods.