laugh
verb
lɑːf 
læf 
1 [intransitive, transitive] to make the sounds and movements of your face that show you are happy or think something is funnyto laugh loudly/aloud/out loudlaugh (at/about something) You never laugh at my jokes!The show was hilarious—I couldn't stop laughing.She always makes me laugh.He burst out laughing (= suddenly started laughing).She laughed to cover her nervousness.I told him I was worried but he laughed scornfully.+ speech ‘You're crazy!’ she laughed.2 [intransitive] be laughing (informal) used to say that you are in a very good position, especially because you have done something successfullyIf we win the next game we'll be laughing.Idioms
don't make me laugh
(informal) used to show that you think what somebody has just said is impossible or stupid‘Will your dad lend you the money?’ ‘Don't make me laugh!’he who laughs last laughs longest
(saying) used to tell somebody not to be too proud of their present success; in the end another person may be more successfullaugh all the way to the bank
(informal) to make a lot of money easily and feel very pleased about itlaugh in somebody's face
to show in a very obvious way that you have no respect for somebody
laugh like a drain
(British English) to laugh very loudlylaugh on the other side of your face
(British English, informal) to be forced to change from feeling pleased or satisfied to feeling disappointed or annoyedHe'll be laughing on the other side of his face when he reads my letter.laugh somebody/something out of court
(British English, informal) to completely reject an idea, a story, etc. that you think is not worth taking seriously at allAll his attempts at explanation were simply laughed out of court.laugh till/until you cry
to laugh so long and hard that there are tears in your eyes
laugh up your sleeve (at somebody/something)
(informal) to be secretly amused about somethinglaugh your head off
to laugh very loudly and for a long time
not know whether to laugh or cry
(informal) to be unable to decide how to react to a bad or unfortunate situationyou have/you've got to laugh
(informal) used to say that you think there is a funny side to a situationWell, I'm sorry you've lost your shoes, but you've got to laugh, haven't you?Phrasal verbs
laugh at somebody/something
to make somebody/something seem stupid or not serious by making jokes about them/itSynonym
ridiculeEverybody laughs at my accent.She is not afraid to laugh at herself (= is not too serious about herself).laugh something 
off
(informal) to try to make people think that something is not serious or important, especially by making a joke about itHe laughed off suggestions that he was going to resign.
Usage note: Different ways of laughingcackle to laugh in a loud, unpleasant way, especially in a high voicechuckle to laugh quietly, especially because you are thinking about something funnygiggle to laugh in a silly way because you are amused, embarrassed or nervousguffaw to laugh noisilyroar to laugh very loudlysnigger/snicker to laugh in a quiet unpleasant way, especially at something rude or at someone’s problems or mistakestitter to laugh quietly, especially in a nervous or embarrassed wayYou can also be convulsed with laughter or dissolve into laughter when you find something very funny. In British English people also shriek with laughter or howl with laughter.