| en friction vector (n) | 
            ― IsA ⟶
         
            Weight: 1.0
         |  | Source: OpenCyc 2012 | ||
| en static friction (n) | 
            ― IsA ⟶
         
            Weight: 1.0
         |  | Source: OpenCyc 2012 | ||
| en surface force vector (n) | 
            ― IsA ⟶
         
            Weight: 1.0
         |  | Source: OpenCyc 2012 | ||
