inflection
noun(also inflexion especially in British English)
[countable, uncountable]a change in the form of a word, especially the ending, according to its grammatical function in a sentence （尤指词尾的）屈折变化 a change in how high or low your voice is as you are speaking 语调的抑扬变化 She spoke slowly and without inflection. 她说得很慢, 声调没有抑扬变化
Word Originlate Middle English (in the sense ‘the action of bending inwards’): from Latin inflexio(n-), from the verb inflectere ‘bend in, curve’, from in- ‘into’ + flectere ‘to bend’.