n.

1. 擴展；擴張；膨脹[U]
   The new factory is large, to allow room for expansion.

   新工廠很大，有地方可以擴展。

2. 擴大物[C]
   The suburbs are an expansion of cities.

   郊區是城市的延伸。

n.

1. the action or an instance of expanding.
   ▸the political strategy of extending a state's territory by encroaching on that of other nations.
2. the increase in the volume of fuel on combustion in the cylinder of an engine, or the piston stroke in which this occurs.