a part added at the end of a book or periodical <there's an addendum from the author to explain certain stylistic choices that she made>
something added (as by growth) <with each new addendum the list of demands simply got more absurd> Synonyms accretion
Related Words accumulation
Seen & Heard
What made you want to look up addendum? Please tell us where you read or heard it (including the quote, if possible).