An intact male bovine is called a bull. A young male bovine is called a bullock. A mature female that has given birth to at least one or two calves is called a cow. A young bovine between birth and weaning is called a calf. Two or more of these young bovines are calves. A female that has never had a calf is called a heifer, (pronounced "heffer"). Calving is the act of a cow or heifer giving birth to a calf.