The term neutral vowel usually refers to an unstressed vowel sound, represented in pronunciation guides like the International Phonetic Alphabet by the schwa symbol /ə/. In phonetics, the schwa is defined as a mid-central unrounded monophthong, i.e., a vowel phoneme formed with the tongue in the rest position, with lips unrounded; for example, the io in nation or the a in about.

More generally, a neutral vowel may refer to any unstressed vowel sound with an indefinite quality, such as the close central unrounded vowel /ɨ/ (roses, orange in certain accents).1 As far as I'm aware, "neutral vowel" when used in this sense is not a formally defined term.

In the study of vowel harmony, a neutral vowel is a vowel that may occur with front and back vowels in a given word.



References

1"neutral, n. and adj.". OED Online. November 2010. Oxford University Press. 9 December 2010

Log in or register to write something here or to contact authors.