Definitions for "Identical twins"
two fetuses produced from the same ovum.
Two offspring created when a single fertilized egg divides to form two separate embryos during the first 2 weeks after conception. Identical twins account for about 30% of naturally occurring twins in the United States.
Results from the splitting of a single fertilised ovum (egg), and each half is identical with the other. Identical twins are extremely important for research purposes; they are always the same sex.