identical twin

Identical twins are siblings who are born at the same time, from the same mother, and who are genetically the same. It can be hard to tell one identical twin from the other, because they look alike.

There are two types of twins: fraternal twins, who look different, and identical twins, who look very similar to each other. All twins are carried at the same time by their mother, but identical twins also have the exact same DNA, or genes, because they develop from the same fertilized egg. Identical twins are also called monozygotic or monozygous twins. The adjective identical comes from the Medieval Latin identicus, which means "the same."

Definitions of identical twin

n either of two twins developed from the same fertilized ovum (having the same genetic material)

monozygotic twin, monozygous twin
Siamese twin, conjoined twin
one of a pair of identical twins born with their bodies joined at some point
Type of:
either of two offspring born at the same time from the same pregnancy

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