the sound changes produced by the rise and fall of the voice when speaking, especially when this has an effect on the meaning of what is said

The end of a sentence that is not a question is usually marked by falling intonation. 非疑问句的句尾通常用降调。

the degree to which the notes of a piece of music are played or sung exactly in tune

The violinist had good intonation, and a wonderful pure tone. 这位小提琴演奏家对音准把握得很好，音色也很纯。