bulwark
/ˈbʊlwək/noun
1- a defensive wall堡垒, 壁垒。
1.1
- figurative a person, institution, or principle that acts as a defence〈喻〉精神堡垒, 支柱：
the security forces are a bulwark against the breakdown of society.
安全部队是防止社会崩溃的堡垒。
1.2
- （一般作bulwarks）an extension of a ship's sides above the level of the deck舷墙。
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