That is one of a few names for it. The Latin word refers to flour. Plants with a powdery coating on the surface are usually called glaucous (or at least that is my usual go-to word).
The white powdery waxy stuff that rubs off (as in Tiffany's pic) is kind of like sunscreen and waterproofing all in one. It will usually be more intense in full sun. It appears on a wide variety of succulents, which are usually in the range from pale green to blue to white. It can provide very effective camouflage for mealy bugs (word to the wise).
