boom/ buːm /

1.noun [c] 
(noise) 轰轰声

2.noun [经济] 
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3.noun
(in prices,popularity) 兴盛

4.vi.[guns] [ thunder+] 
(also: boom out) 发出隆隆的响声

5.vi.[voice+] 
发出低沉有力的声音

6.vi.[sales] [ business] [ economy+] 
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