1. Fall down, as if collapsing
   "The tower of the World Trade Center toppled after the plane hit it";
   - tumble
    
2. Cause to topple or tumble by pushing
   "The wind toppled the stack of newspapers";
   - tumble, tip

Derived forms: toppled, topples, toppling

Type of: come down, descend, force, go down, push

Encyclopedia: Topple