脊柱前凸；穹状书脊；腔背

腔背，穹状书脊（书背和书本身不粘在一起的精装，各国现在一般均通行这种形式，日本称之为腔背）

hollow backs───脊柱前凸；穹状书脊；腔背

hollow-back───脊柱前凸；穹状书脊；腔背

hollow-backed───脊柱前凸；穹状书脊；腔背

to plow back───向后犁

hold back───隐瞒；退缩；抑制；阻止

holds back───隐瞒；退缩；抑制；阻止

low back───腰部

plow back───盈余再投资

roll back───击退；把…压低到标准水平

Back then they were made of naturally occurring objects - coconuts, sea shells, hollow stones or similar objects filled with moss or a similar material that was soaked with animal fat and ignited.───当时的它们是由天然材料制成的——椰子，贝壳，镂空的石头或相似的物体，里面装满苔藓，地衣或同样能吸收动物脂肪且容易点燃的材料。

I sneaked out a quart jar of peaches, some cold corn bread, and a few Onions, and started up the hollow back of our house.───我偷了一罐桃子、几块冷玉米面包和一些洋葱，打算从后门走。

Hollow back the normal cased book is a hollow back but this is assumed and therefore not specified. See back.───一般精装书籍均假定为空背，不用特别说明。参阅书背。

Open back: Common style of case bound book . Also called Hollow back.───空背: 一般精装书籍均假定为空背,不用特别说明.

Open back: Common style of case bound book . Also called Hollow back.