From nine + -plex. <span class="searchmatch">nineplex</span> (plural nineplexes) (US) A building divided into nine separate residences or commercial premises....
lipoplex megaplex metroplex microplex monoplex motorplex multiplex nanoplex <span class="searchmatch">nineplex</span> nonaplex n-plex pentaplex plex quadplex quadruplex quintuplex sevenplex...