Is it ensure, insure, or assure?
1840, from French glucose (1838), said to have been coined by French professor Eugène Melchior Péligot (1811-1890) from Greek gleukos "must, sweet wine," related to glykys "sweet, delightful, dear," from *glku-, dissimilated in Greek from PIE *dlk-u- "sweet" (cf. Latin dulcis). It first was obtained from grape sugar.
glucose glu·cose (glōō'kōs')
A monosaccharide sugar the blood that serves as the major energy source of the body; it occurs in most plant and animal tissue. Also called blood sugar.
A monosaccharide sugar found in plant and animal tissues. Glucose is a product of photosynthesis, mostly incorporated into the disaccharide sugar sucrose rather than circulating free in the plant. Glucose is essential for energy production in animal cells. It is transported by blood and lymph to all the cells of the body, where it is metabolized to form carbon dioxide and water along with ATP, the main source of chemical energy for cellular processes. Glucose molecules can also be linked into chains to form the polysaccharides cellulose, glycogen, and starch. Chemical formula: C6H12O6. See more at cellular respiration, Krebs cycle, photosynthesis.