Unequal conjoined twins in which the smaller parasite is wholly or partly within the abdomen of the larger autosite. ... Origin: G. En, in, + gaster, belly ... (05 Mar 2000) ... 
(en-gas´tre-әs) a double fetus in which one fetus is contained within the abdomen of the other.
Type: Term Pronunciation: en-gas′trē-ŭs Definitions: 1. Unequal conjoined twins in which the smaller parasite is wholly or partly within the abdomen of the larger autosite.