carbohydrate
UK: ˌkɑːbəʊˈhaɪdreɪt | US: ˌkɑːrboʊˈhaɪdreɪt
n. A biological molecule consisting of carbon, hydrogen, and oxygen atoms, typically with a hydrogen-oxygen ratio of 2:1 (e.g., sugars, starches).
n. (Nutrition) A macronutrient found in foods like grains, fruits, and vegetables, serving as a primary energy source.
The term "carbohydrate" emerged in 19th-century chemistry, combining "carbo-" (from Latin carbo, meaning "coal" or "carbon") and "-hydrate" (from Greek hydor, "water"). Early chemists observed that these compounds (e.g., glucose) had a molecular formula resembling carbon ("carbo") combined with water ("hydrate"), e.g., C₆H₁₂O₆ = 6C + 6H₂O. Though modern chemistry reveals a more complex structure, the name reflects this historical observation.
Whole grains are a rich source of complex carbohydrates.
Athletes often consume carbohydrates before endurance events.
Photosynthesis converts sunlight into carbohydrates in plants.
A low-carbohydrate diet restricts foods like bread and pasta.
Cellulose, a carbohydrate, provides structural support in plant cell walls.