prokaryote

Concise Oxford English Dictionary © 2008 Oxford University Press:
prokaryote /prəʊˈkarɪəʊt, -ɒt/ (also procaryote)

▶noun Biology a single-celled organism with neither a distinct nucleus with a membrane nor other specialized structures (i.e. a bacterium or archaean). Compare with eukaryote.

– derivatives
prokaryotic adjective.

– origin 1960s: from pro-2 + Gk karuon ‘nut, kernel’ + -ote as in zygote.