volatile

(noun): A chemical or compound that changes into a gas easily.
(adjective): Evaporating or vaporizing readily under normal conditions.
(adjective): (of a substance) Explosive.
(adjective): (of a price etc) Variable or erratic.
(adjective): (of a person) Quick to become angry or violent.
(adjective): Fickle.
(adjective): Temporary or ephemeral.
(adjective): (of a situation) Potentially violent.
(adjective): (of a variable) Having its associated memory immediately updated with any changes in value.
(adjective): (of memory) Whose content is lost when the computer is powered down
(adjective): Passing through the air on wings, or by the buoyant force of the atmosphere; flying; having the power to fly.