Also found in: Dictionary, Thesaurus, Encyclopedia, Wikipedia.
monozygotic twins whose bodies are joined. The connection may be slight or extensive; it may involve skin and muscles or cartilage of a limited region, such as the head, chest, hip, or buttock, or the twins may share an organ, such as an intestine or parts of the spine. If joined superficially, the twins may be easily separated by surgery soon after birth. If more deeply united, they may have to go through life with their handicap, if they survive. New techniques in surgery are making it possible to separate some Siamese twins whose physical links are highly complex. Called also conjoined twins
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.
originally, a much-publicized conjoined pair of twins (xiphopagus) born in Siam (present-day Thailand) in the 19th century; this term has since come into general lay usage for any type of conjoined twins, but is incorrect.
Farlex Partner Medical Dictionary © Farlex 2012
Prognosis Depends on the need for or adequacy of surgical separation
Segen's Medical Dictionary. © 2012 Farlex, Inc. All rights reserved.
'Siamese' twinsConjoined equal twins A joined gestational product due to a failure in division of the yolk sac or due to delayed monovular separation; STs occur in ±1:200,000 term deliveries; most are joined at the chest–thoracopagus Prognosis Depends on adequacy of surgical separation
McGraw-Hill Concise Dictionary of Modern Medicine. © 2002 by The McGraw-Hill Companies, Inc.
Si·a·mese twins(sī'ă-mēz' twinz)
A much publicized pair of conjoined twins born in Thailand (then Siam) in the 19th century; this term has since come into general lay usage for any type of conjoined twins.
Medical Dictionary for the Health Professions and Nursing © Farlex 2012
Siamese twinsIdentical (monozygous) twins that have failed fully to separate after the first division of the ovum and remain partially joined together at birth. The junction is usually along the trunk or between the two heads. From the male twins, Chang and Eng, born in Siam in 1811.
Collins Dictionary of Medicine © Robert M. Youngson 2004, 2005
Siamese twins,named for Eng and Chang (1811-1874) who were born in Siam (now Thailand).
Medical Eponyms © Farlex 2012