backbone road

基本解释

He slipped end-over-end as the gaps in the road, it is a backbone.
涵管做为道路中的空隙，它是一个脊梁。
The new road is part of the backbone of China's national highway system, scheduled for completion this year.
新的道路是定于今年完工的全国高速公路主干网的一部分。
blog.sina.com.cn
The traffic network composed of four lengthwise and three transverse roads has been built in the Base, including one landscape backbone road with planned overall length of 5 km and width of 35 m.
基地内已经建成四纵三横的道路网架，其中一条为规划全长5公里，宽为35米的景观主干道。