(Latin: coal, charcoal)
Carbohydrates are made up of carbon, hydrogen, and oxygen in a ratio of approximately one carbon, two hydrogen, and one oxygen.
Sugar, starch, and cellulose constitute the carbohydrates. Sugars are classified according to whether or not they can be decomposed in a water solution.
Simple sugars or monosaccarides cannot be so decomposed; complex sugars or polysaccarides can be broken down by water or hydrolysis. The most common simple sugars are glucose and fructose. See saccharo- for more details.
Glucose is also called dextrose, and fructose is also known as levulose. The common white commercial sugar is sucrose, which is a disaccharide or double sugar; a combination, actually, of a glucose and a fructose molecule.
Teachers used to use paper impregnated with a carbonaceous substance to make copies of exercise sheets for their students.
2. A group of boils is known as a carbuncle.
3. A red gemstone, especially a garnet, which is smoothly rounded and polished.
4. Etymology: from Old French charbu(n)cle and Latin carbunculus, "small coal"(carbon- "coal").