pepper spray       
 noun [ U ] (also pepper-spray) uk/ˈpep.ə ˌspreɪ/ us/ˈpep.ɚ ˌspreɪ/
 胡椒喷雾剂
a chemical based on a substance found in hot peppers, in a container that can be sprayed (= forced out in small drops) into a person's face. This causes pain and tears in the eyes and can be used by police or as a method of self-defence.
  Police had to use pepper spray to break up the brawl. 警察不得不使用胡椒喷雾来分开斗殴的人群。 
 - More examples
 - Some airline workers want permission to carry pepper spray to keep threatening passengers in line.
 - When he tried to get on stage, a member of the singer's entourage attacked him with pepper spray.
 - Both women said they feel more confident walking alone now they carry pepper spray.
 - There were allegations of misuse of pepper-spray against protesters.
 
pepper spray       
verb [ T ] (also pepper-spray) uk/ˈpep.ə ˌspreɪ/ us/ˈpep.ɚ ˌspreɪ/
 使用胡椒喷雾剂
to spray someone with pepper spray
  He claims the crowd were tear-gassed and pepper sprayed by guards without warning.  他声称,人群在没有警告的情况下被保安施以催泪瓦斯和胡椒喷雾。 
 - More examples
 - She found the man attempting to sexually assault a 28-year-old woman in a hallway, pepper sprayed him and held him down until officers could arrive.
 - What drove the officer to beat the 15 year old with her baton and pepper spray him?
 - "I'm being nonviolent, and this officer is going to pepper-spray me!" he told reporters.