Frost ice is the result of water freezing on unprotected surfaces.

He had observed a patch of unprotected surfaces, there, exposed just below the wing.

It's a very shortwave form of light, which allows it to penetrate through soft, unprotected surfaces in search of entertainment.

He would have to step out onto the unprotected surface of a planet in daytime.

The planet was still very dangerous over all of its unprotected surface, since the Fwndyri had thoroughly seeded it with nanophages.

So we could actually go through the elaborate airlocks and step out onto the blasted surface unprotected.

Hence, unprotected surfaces can be seen in shades of gray.

On an unprotected surface, bacteria can double in number every 20 minutes.

When he looked out on the unprotected surface of Pandora, there was no denying its immediate dangers.

The product is sprayed directly onto the unprotected surface.