]> A small spherical particle of any liquid; in meteorology, particularly a water droplet. Said of two or more liquids that are mutually soluble (i.e. they will dissolve in each other) (McGraw-Hill, 1974). The chemical property of two or more phases that, when brought together, have the ability to mix and form one phase (after AGI, 1980). Any substance existing in the gaseous state at a temperature lower than that of its critical point; that is, a gas cool enough to be liquefied if sufficient pressure were applied to it.