noun
ablaut; vowel gradation; apophony
Linguistic term for systematic vowel changes within a root, such as sing/sang/sung. Rare in general use; mainly encountered in academic contexts.
英語の不規則動詞には母音交替が見られる。
Ablaut can be seen in English irregular verbs.
noun
vowel shift
Refers to a historical or systematic change in vowel pronunciation, such as the Great Vowel Shift. Also a technical term.
大母音推移は英語の母音交替の一例である。
The Great Vowel Shift is an example of a vowel shift in English.