Main Entry: vitamin B12

Pronunciation: \-ˈbē-ˈtwelv\

Function: noun

Date: 1948

1 : a complex cobalt-containing compound C₆₃H₈₈CoN₁₄O₁₄P that occurs especially in liver, 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