1. (Be) in stitches: to laugh

2. Belly-laugh: to laugh in a deep, hearty manner, as if from the abdomen or in such a way that one's abdomen moves from the exertion

3. Break up: to laugh as if helplessly

4. Cachinnate: to laugh loudly and/or obnoxiously

5. Cackle: to laugh harshly or sharply

6. Chortle: to chuckle or to otherwise laugh to express satisfaction or triumph

7. Chuckle: to laugh mildly and/or quietly

8. Crack up: see "break up"

9. Crow: to laugh derisively or gloatingly

10. Giggle: to laugh with short, repetitive sounds

11. Guffaw: to laugh boisterously and/or loudly

12. Hee-haw: a synonym for guffaw

13. Horselaugh: To laugh in a way suggestive of or in imitation of a horse's neighing or whinnying

14. Jeer: to laugh disrespectfully or mockingly

15. Scoff: to laugh derisively or dismissively

16. Snicker: to partially suppress a laugh, as if to conceal one's mirth

17. Snigger: an alteration of snicker, with the additional connotation of mischief

18. Split (one's) sides: to laugh convulsively, as if continuing to do so will cause one's body to rupture

19. Titter: to laugh in an affected manner, or nervously; also a synonym of snicker and snigger

20. Twitter: a synonym of giggle or titter, but also means to chatter or to tremble as if agitated

21. Fake laughter

22. Evil laughter

23. Hysterical laughter

24. Inappropriate laughter

25. Baby laughter

26. Nervous laughter

27. Silent laughter

28. Teasing laughter

29. Etiquette laughter

30. Contagious laughter

31. Belly laughter