backbone

/ˈbækˌboʊn/

a central cohesive source of support and stability

Chinese meaning: 支柱；骨干；脊柱

Small businesses are the backbone of the local economy, providing jobs and services.

小企业是当地经济的支柱，提供就业和服务。

The spine, or backbone, protects the spinal cord and supports the body.

脊柱保护脊髓并支撑身体。