gas, gaseous state -- (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)
gas -- (a fluid in the gaseous state having neither independent shape nor volume and being able to expand indefinitely)
gasoline, gasolene, gas, petrol -- (a volatile flammable mixture of hydrocarbons (hexane and heptane and octane etc.) derived from petroleum; used mainly as a fuel in internal-combustion engines)
flatulence, flatulency, gas -- (a state of excessive gas in the alimentary canal)