jupiter
All of the planets except Mercury and Venus, which have no moons, have at least one moon that lacks an atmosphere.
The Earth is the only planet in our Solar System with one Moon
Titan, the moon of saturn, has an atmosphere. however, Triton has a very thin nitrogen one, and even the moon has one (thinner than that of mercury, so it's really not that big, but it is technically an atmosphere.)
The only planet with one moon is Earth. The smallest planet is Mercury but it doesn't have any moons.
Earth is the major planet in our solar system that has only one moon, which is called the Moon.
Only Earth has exactly one moon.
Within our Solar System, the Earth is the only planet with one moon.
Only Earth has exactly one moon.
Many planets have only one moon. For example, Earth only has one moon. There are likely to be billions of planets in our universe with just one moon. As you can imagine, the list of these would take a long time to write out. We will only have discovered a small amount of actual planets that fit this description though.
Earth
Well no outer planet has only one moon they all either have more than 1 or none at all.
No known planets have only one moon other than earth.