柯林斯词典cavity wall 1. N a wall that consists of two separate walls, joined by wall-ties, with an airspace between them 空心牆 返回 cavity wall剑桥词典a wall of a building formed from two walls with a space , usually for air , between them. It is made in this way to keep out water and cold air . （防溼防寒的）空心牆，夾層牆 返回 cavity wall