柯林斯词典bursa /ˈbɜːsə/ 1. N a small fluid-filled sac that reduces friction between movable parts of the body, esp at joints (尤指关节处的)滑囊 返回 bursa剑桥词典a sac (= part of the body like a bag ) that is filled with fluid and protects tissue from injury due to friction 囊 返回 bursa