White frost; hoarfrost; congealed dew or vapor.

To freeze or congeal into hoarfrost.

A dense, fine-grained deposit built up from the freezing of supercooled cloud droplets onto exposed objects, including falling snow crystals.

ice crystals forming a white deposit (especially on objects outside)

a little Styrofoam-like pellet which results when a snowflake falls through a cloud with a great deal of super cooled water vapor, and it's heavily lined

a deposit of ice formed when supercooled water droplets freeze on contact with an object

Ice that forms when supercooled fog or cloud droplets come into contact with an object.

Deposits of ice, composed of grains more or less separated by trapped air, sometimes with crystalline appearance assuming the forms needles or scales. Formed by freezing of supercooled water droplets of surrounding moist air (fog or clouds).

more info Supercooled water droplets that freeze to snowflakes in a cloud. Rimed snow often has a fuzzy appearence.

Tiny balls of ice that form when tiny drops of water freeze on contact with the surface.

An accumulation of granular ice tufts on the windward sides of exposed objects that is formed from supercooled fog or cloud and built out directly against the wind.

thin layer of ice and hard snow over rock

a white or milky and opaque granular deposit of ice formed by the rapid freezing of super-cooled water drops as they impinge upon an exposed object; it is denser and harder than hoarfrost, but lighter, softer, and less transparent than glaze.

The rapid freezing of supercooled water droplets as they touch an exposed object, forming a white opaque granular deposit of ice. It is one of the results of an ice storm, and when formed on aircraft it is called rime icing.

Rime ice is a white ice that forms when the water droplets in fog freeze to the outer surfaces of objects. It is often seen on trees atop mountains and ridges in winter, when low-hanging clouds cause freezing fog. This fog freezes to the windward (wind-facing) side of tree branches, buildings, or any other solid objects.