Sublimation is the transition from the solid to the gas state. A good example is carbon dioxide ice. The opposite of this process is called deposition : the transition from the gas to the solid.

Condensation is the transition from gas to liquid as in the condensation of steam to liquid water. Vaporization is the opposite from the liquid to the gas state. Melting is from the solid to the liquid state and freezing from liquid to solid.

Yes, there is an opposite to sublimation as a phase change, when a gas condenses directly to the solid phase bypassing the liquid. I have found that some name this change deposition, but the term is not frequently used. You can read more about this at

Certainly the reverse process must be possible (i.e. going from a gaseous state directly to a solid state) but I don't think there is a name for it. "Sublimation" may actually refer to going in both directions. One example I can imagine would be water vapor in the upper atmosphere where the pressure is low. If the temperature drops, the vapor would freeze without going to the liquid state first.

There is an opposite to sublimation. It is similar to condensation, except the substance goes directly from vapor to solid. The formation of frost is a good example:

If warm, humid air (such as your breath) blows over a cold surface (such as a piece of metal kept in the freezer), ice will condense onto the surface directly from the vapor. Snow forms in a similar way. If air temperature must fall below freezing to reach 100% humidity, then snow can form by reverse sublimation as the temperature falls through the point of 100% humidity. If the point of 100% humidity is above freezing, rain forms as the temperature falls. This is the opposite of evaporation. In either case, the "surface" is provided by dust or other microscopic particles in the atmosphere. Each particle seeds its own snowflake or raindrop.