Noun
1. slaughter
3. indiscriminate killing
4. mass murder
5. mass execution
6. annihilation
10. carnage
11. butchery
12. bloodbath
13. bloodletting
14. pogrom
15. genocide
16. ethnic cleansing
17. holocaust
Verb
20. slaughter
21. butcher
22. murder
23. kill
24. annihilate
25. exterminate
26. execute
27. liquidate
28. eliminate
29. decimate
30. wipe out
31. mow down
32. cut down
33. put to the sword
34. put to death
35. slay