Definition of "Superfetation" :
noun: fertilization of a second ovum after a pregnancy has begun; results in two fetuses of different ages in the uterus at the same time
"Superfetation is normal in some animal species."
noun: fertilization of a second ovum after a pregnancy has begun; results in two fetuses of different ages in the uterus at the same time
"Superfetation is normal in some animal species."