WordNet sense 1 (a fossil fuel in the gaseous state; used for cooking and heating homes):

natural gas

WordNet sense 2 (a volatile flammable mixture of hydrocarbons (hexane and heptane and octane etc.) derived from petroleum; used mainly as a fuel in internal-combustion engines):

gasoline, petrol, gasolene

WordNet sense 3 (the state of matter distinguished from the solid and liquid states by: relatively low density and viscosity; relatively great expansion and contraction with changes in pressure and temperature; the ability to diffuse readily; and the spontaneous tendency to become distributed uniformly throughout any container):

gaseous state

WordNet sense 4 (a state of excessive gas in the alimentary canal):

flatulence, flatulency

WordNet sense 5 (a pedal that controls the throttle valve):

accelerator, gun, throttle, accelerator pedal, gas pedal

WordNet sense 6 (show off):

blow, bluster, boast, brag, gasconade, swash, tout, vaunt, shoot a line