GW sometimes refers to one of two Presidents of the United States:

George Washington

George Washington summary and related information.

George W. Bush

Games Workshop, a publicly traded company that makes wargames.

The George Washington Bridge across the Hudson River.

GW is the abbreviation for The George Washington University in Washington, D.C.

The symbol for gigawatt, a unit for measuring power, equal to 10⁹ watts

The Internet top-level domain of Guinea-Bissau (.gw)

A USCS symbol for well graded gravels

Guild Wars, an episodic series of multiplayer online role-playing games.