Wiktionary
episome
n. (context cytology English) A segment of DNA that can exist and replicate either autonomously in the cytoplasm or as part of a chromosome, mainly found in bacteria.
Wikipedia
Episome (album)
Episome is a collaborative album by Bill Laswell, Otomo Yoshihide and Tatsuya Yoshida. It was released on April 18, 2006 by Tzadik Records.