Glucose (noun). a variety of sugar occurring in nature very abundantly, as in ripe grapes, and in honey, and produced in great quantities from starch, etc., by the action of heat and acids. It is only about half as sweet as cane sugar.Called also dextrose, grape sugar, diabetic sugar, and starch sugar.tarch and cellulose are polymers derived from the dehydration of D-glucose. The other stereoisomer, called L-glucose, is hardly ever found in nature. The name glucose comes from the Greek word glukus, meaning sweet.