Source : Webster's Revised Unabridged Dictionary (1913)

Gaseous \Gas"e*ous\ (? or ?; 277), a. [From {Gas}. Cf. F.
   gazeux.]
   1. In the form, or of the nature, of gas, or of an
      a["e]riform fluid.

   2. Lacking substance or solidity; tenuous. ``Unconnected,
      gaseous information.'' --Sir J. Stephen.

Source : WordNet®

gaseous
     adj : existing as or having characteristics of a gas; "steam is
           water is the gaseous state" [ant: {solid}, {liquid}]