모음 축약에 대한 통시적 연구

A Diachronic Study on the Vowel Contraction

This paper reviewed the process of vowel contraction and glide formation which occurred during the change of downward diphthong 'ㅔ, ㅐ, ㅟ, and ㅚ' in medieval Korean into monophthong. The change of 'ㅕ>ㅔ' is not into '[jə]>[jəj](addition of i)>[je](monophthongization of '에')>[e](on-glide j elimination)' but into a direct contraction. The change of 'VjV>ɛ:, VjV>ja:' appeared in two forms including ① aja>ɛ(j)a>ɛ(j)ɛ>ɛ: ② aja>ɛ(j)a>eja>ija>ja:. 'ㅟㅓ>􎷚' is a diachronic phenomenon which is explained with the glide formation of ɥ. The change of 'ㅕ>ㅔ', 'VjV>ɛ, VjV>ja', 'ㅟㅓ>􎷚' may be explained as a transformation which appeared during the change of a vowel system, namely the monophthongization of a diphthong. The appearance of various variation types before and after the occurrence of the monophthongization of 'ㅔ, ㅐ, ㅟ, and ㅚ' is caused by the instability of the vowel system.