When you laugh, you make a sound with your throat while smiling and show that you are happy or amused. People also sometimes laugh when they feel nervous or are being unfriendly.

If people laugh at someone or something, they mock them or make jokes about them.

If you do something for a laugh or for laughs, you do it as a joke or for fun.

If a person or their comment gets a laugh or raises a laugh, they make the people listening to them laugh.

If you describe a situation as a laugh ,a good laugh, or a bit of a laugh, you think that it is fun and do not take it too seriously.

If you describe someone as a laugh or a good laugh, you like them because they are amusing and fun to be with.

If you have a good laugh about something, you find it amusing and realize that it is funny, especially when the situation was at first upsetting.

If you say that you have the last laugh, you mean that you become successful at something so that people who criticize or oppose you look foolish.

Some people reply to other people's comments or opinions by saying 'Don't make me laugh' when they disagree with them and think they are foolish or inaccurate.

If you say 'you've got to laugh' or 'you have to laugh', you are trying to see the amusing side of a difficult or disappointing situation rather than being sad or angry about it.