noun, plural: nucleoids
The portion within a prokaryotic cell where the genetic material is to be found.
In contrast to eukaryotes with a nucleus, prokaryotes have a nucleoid where the genetic material can be found. The nucleoid is different from the nucleus of the eukaryotes in a way that the genetic material is not enclosed in a membrane to separate it from the cytoplasm.
Word origin: nucleo- + -oid; thus "like a nucleus".
Related forms: nucleoidal (adjective)