Dextrose Monohydrate (D-glucose) is a sugar that's a stable, odorless, white crystalline powder or colorless crystal.
In its pure form, it has a dextrose equivalency (DE) of 100, which indicates that it's 100% pure Dextrose, not a mixture with other substances as well. Dextrose equivalency is a good value to know when purchasing Dextrose supplies.
Dextrose is commercially available in monohydrate or anhydrate form, termed Dextrose Monohydrate or Dextrose Anhydrate, respectively.
Note: "Hydrate" is a term used by industry professionals to indicate the degree to which a substance contains water.
Monohydrate substances contain one water molecule, referred to as a molecule of water of hydration. These water molecules are said to be "coordinated" to the substance, which indicates a type of loose chemical linkage.
Dextrose Monohydrate is a sugar that contains one molecule of water per dextrose molecule, i.e. for every dextrose molecule, there is a water molecule loosely linked.
If a material is deemed anhydrate, it doesn't contain water. Dextrose is available in the anhydrate form as well, a.k.a. Dextrose Anhydrate; however, it's used mainly in the pharmaceutical industry.