ad ‧ den ‧ dum /əˈdendəm/ BrE AmE noun ( plural addenda /-də/ or addendums ) [countable]
[ Date: 1600-1700 ; Language: Latin ; Origin: addere ; ⇨ ↑ ADD ]
something you add to the end of a speech or book to change it or give more information
addendum to
an addendum to section 4