one of a pair of twins, not necessarily resembling each other, or of the same sex, that develop from two separately fertilized ova.
Wonder TwinsRead more in this article about some frequently asked questions and fun facts related to our definitions.
What Are Some Words For Sibling Pairs?These days, giving birth to twins is increasingly common. As many as 5 out of every 1,000 babies born shared a womb with their sibling. While cute and adorable are some starter words to use when welcoming new babies, here's a look at the lexicon to haul out when welcoming multiples!
Compare identical twin.
Origin of fraternal twin
First recorded in 1900–05
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
Medicine definitions for fraternal twins
Twins that derive from separately fertilized ova and that have different genetic makeup. They may be of the same or opposite sex.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.