A carbenoid is a reactive intermediate in organic chemistry that resembles a carbene but has different properties. Carbenes are species with a carbon atom that has two unshared electrons, making them highly reactive. Carbenoids, on the other hand, often contain a metal atom, which stabilizes the structure and allows for various chemical reactions, such as insertion reactions. Carbenoids are commonly used in synthetic chemistry, particularly in organometallic chemistry. They can facilitate the formation of new carbon-carbon bonds, making them valuable in the synthesis of complex organic molecules. Their unique reactivity and stability make them important tools for chemists in developing new compounds.