A wall built for protection or defense, typically between two opposing or warring sides; a defensive barrier. Also called a 隔离墙 gé​lí​qiáng.

A defensive wall or parapet built at the top of a fortification.

(abbreviation) A nutritional concept in mainland China advocating the consumption of purple vegetables and fruits to boost the immune system; short for 紫色蔬菜健康防卫墙 zǐ​sè​shū​cài​jiàn​kāng​fáng​wèi​qiáng.