co ‧ dex /ˈkəʊdeks $ ˈkoʊ-/ BrE AmE noun ( plural codices /-dəsiːz, -dɪsiːz/) [countable] technical
[ Date: 1500-1600 ; Language: Latin ; Origin: 'main part of a tree, piece of wood for writing on, book' ]
an ancient book written by hand:
a sixth-century codex