conjoined twins

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con·joined twins

monozygotic twins with varying extent of union and different degrees of residual duplication. The various types of union are named by the use of a prefix designating the region that is united and adding the suffix -pagus, meaning joined (for example, craniopagus [united by the heads], thoracopagus [united in thoracic region]); the various types of residual duplication are named by designating the parts duplicated and adding the suffix -didymus, or -dymus, meaning twin (for example, cephalodidymus, cephalodymus).

conjoined twins

two fetuses developed from the same ovum who are physically united at birth. The defect ranges from a superficial anatomical union of varying extent between equally or nearly equally formed fetuses to one in which only a part of the body is duplicated or in which a small, incompletely developed fetus, or parasite, is attached to a more fully formed one, the autosite. Conjoined twins result when separation of the blastomeres in early embryonic development does not occur until a late cleavage phase and is incomplete, causing the fused condition. Viability depends on the extent of the fusion and the degree of development of the fetuses. See also Siamese twins.
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Conjoined twins at 12 weeks of development

con·joined twins

(kon-joynd' twinz)
Monozygotic twins with varying extent of union and different degrees of residual duplication. The various types of union are named by the use of a prefix designating the region that is united and adding the suffix -pagus, meaning fused (e.g., craniopagus, thoracopagus); the various types of residual duplication are named by designating the parts duplicated and adding the suffix -didymus, or -dymus, meaning twin (e.g., cephalodidymus, cephalodymus).

conjoined

joined together.

conjoined monsters
two deformed fetuses fused together.
conjoined twins
see conjoined twins.