gaseous

adj. of gas; resembling gas

Gas can also refer to gasoline and natural gasand also hydrogen. For other uses, see gas (disambiguation). Gas is one of the four major states of matter, consisting of freely moving atoms or molecules without a definite shape. Compared to the solid and liquid states of matter a gas has lower density and a lower viscosity. The volume of a gas will change with changes in temperature or pressure, as described by the ideal gas law. A gas also has the characteristic that it will diffuse readily, spreading apart in order to uniformly fill the space of any container.
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Gas may refer to:Science and technologyGas, one of the phases of matterA short form for gasoline (petrol), especially in North AmericaLiquefied Petroleum Gas (LPG), also called "cooking gas", which includes propane and butaneAutogas, a type of LPG used in motor vehiclesNatural gas, a gaseous fossil fuel consisting primarily of methaneThe medical effects of gas being generated in the gastrointestinal tract, including bloating, burping, and flatulence
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(a.)
Lacking substance or solidity; tenuous.
  

(a.)
In the form, or of the nature, of gas, or of an aeriform fluid.
  

Adjective
1. existing as or having characteristics of a gas; "steam is water is the gaseous state"
(antonym) solid
(similar) aeriform, airlike
(attribute) state of matter, state