Siamese twin
noun
(not in technical use) conjoined twin.
Origin of Siamese twin
First recorded in 1820–30; named after congenitally united twins, Chang and Eng (1811–74), born in Siam, who were joined to each other at the chest
British Dictionary definitions for siamese twins
Word Origin for Siamese twins
C19: named after a famous pair of conjoined twins, Chang and Eng (1811–74), who were born in
Siam
Medical definitions for siamese twins
Siamese twin
[ sī′ə-mēz′ ]
n.
Either of a pair of conjoined twins. No longer in technical use.