Conjoined twins in which the two individuals are joined at the buttocks, most often back to back. ... See: conjoined twins. ... Origin: pygo-+ G. Pagos, something fixed ... (05 Mar 2000) ... 
(pi-gop´ә-gәs) conjoined twins fused in the sacral region.
Type: Term Pronunciation: pī-gop′ă-gŭs Definitions: 1. Conjoined twins in which the two individuals are joined at the buttocks, most often back to back. See: conjoined twins, under twin
pygopagous, pygopagus Twins united in the region of the buttocks so that the two are back to back.