laugh, laughing, laughter 这三个词均可用作名词，表示“笑”，但是具体含义是有区别的。

　　

1. laugh 侧重指行为，是可数名词。如：　　

He answered with a laugh.

Is your mother at home? I heard her laugh.

2. laughing 侧重指笑的动作，是不可数名词。如：　　

He held his laughing.

3. laughter 具有抽象或概括意义，是不可数名词 。如：　　

In this case there is no cause for laughter.

The room was full of laughter and happiness.