1. 大屠杀；残杀
You can refer to the cruel killing of a lot of people as butchery when you want to express your horror and disgust at this.

2. 屠宰工作
Butchery is the work of cutting up meat and preparing it for sale.

1. the savage and excessive killing of many people

Synonym: slaughtermassacremass murdercarnage

2. the business of a butcher

Synonym: butchering

3. a building where animals are butchered

Synonym: abattoirshamblesslaughterhouse