Main Entry: vitamin B₁₂

Pronunciation: \-ˈbē-ˈtwelv\

Function: noun

1 : a complex cobalt-containing compound C₆₃H₈₈CoN₁₄O₁₄P found in animal products (as meat and eggs) that is essential to normal blood formation, neural function, and growth and is used especially in treating pernicious and related anemias and in animal feed as a growth factor—called also cyanocobalamin
2 : any of several compounds similar to vitamin B₁₂ in action but having different chemistry