before vowels glyc-, word-forming element meaning "sweet," from Latinized combining form of Greek glykys, glykeros "sweet" (see gluco-). Used in reference to sugars generally. OED says a regular formation would be glycy-.
Entries linking to glyco-
gluco-
before vowels, gluc-, word-forming element used since c. 1880s, a later form of glyco-, from Greek glykys "sweet," figuratively "delightful; dear; simple, silly," from *glku-, a dissimilation in Greek from PIE root *dlk-u- "sweet" (source also of Latin dulcis). De Vaan writes that "It is likely that we are dealing with a common borrowing from an unknown source." Now usually with reference to glucose.
glycemia n.
also glycaemia, "presence or level of sugar in the blood," 1901, from glyco- "sugar" + -emia "condition of the blood."