volatile >> ˈvɒlətʌɪl
Definition: [adjective] (of a substance) easily evaporated at normal temperatures.
Example: volatile solvents such as petroleum ether, hexane, and benzene
Definition: [adjective] liable to change rapidly and unpredictably, especially for the worse.
Example: the political situation was becoming more volatile
Definition: [adjective] (of a computer's memory) retaining data only as long as there is a power supply connected.
Definition: [noun] a volatile substance.