"Conjoined twins" is a term used to describe twins who are physically connected to each other at birth. They share certain body parts or organs which can make their bodies joined together in different ways. Full definition
The figures beyond diprosopia, labeled XII through XIV, illustrate a condition called dicephalus, which turned out not to be an extension of diprosopia, but rather a variant of conjoined twinning Reprinted with permission from Wiley - Liss, Inc., a subsidiary of John Wiley and Sons, Inc.. (newscientist.com)
Forty doctors have successfully separated conjoined twin boys who were attached at the skull in a marathon surgical procedure that lasted more than 36 hours. (dailypost.ng)
«Stuck on You» (20th Century Fox) The Farrelly Brothers cast Matt Damon and Greg Kinnear as conjoined twins. (chron.com)