episome

epi·some

noun \ˈep-ə-ˌsōm, -ˌzōm\

Definition of EPISOME

: a genetic determinant (as the DNA of some bacteriophages) that can replicate either autonomously in bacterial cytoplasm or as an integral part of their chromosomes—compare plasmid

—epi·som·al \ˌep-ə-ˈsō-məl, -ˈzō-\ adjective

—epi·som·al·ly \-mə-lē\ adverb