What do you call a polymer that is made up of two sugar molecules?

A polymer made up of two sugar molecules is specifically termed a disaccharide. Disaccharides are formed when two monosaccharides, which are simple sugars, undergo a condensation reaction, resulting in a glycosidic bond between them. Common examples of disaccharides include sucrose (table sugar), lactose (milk sugar), and maltose.

In contrast, monosaccharides refer to single sugar units and do not qualify as polymers. Oligosaccharides consist of a few (typically 3 to 10) monosaccharide units and are larger than disaccharides but smaller than polysaccharides, which are long chains of monosaccharides (more than ten). Hence, the definition of disaccharide aligns perfectly with the characteristic of containing exactly two sugar molecules.