the basic structural unit of chromatin in eukaryotes, composed of eight histone molecules wrapped by a segment of DNA: nucleosomes occur at intervals along a continuous strand of DNA
See nucleosome in American Heritage Dictionary 4
(no͞oˈklē-ə-sōmˌ, nyo͞oˈ-)
noun
Any of the repeating subunits of chromatin, consisting of a DNA chain coiled around a core of histones.