gas

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

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

a state of excessive gas in the alimentary canal

a pedal that controls the throttle valve; "he stepped on the gas"

a fossil fuel in the gaseous state; used for cooking and heating homes

attack with gas; subject to gas fumes; "The despot gassed the rebellious tribes"

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