Addenda-Addendum | Commonly Confused Words

Addenda

Additional material provided at the end of a book, document, or article

This word has no antonyms

/əˈdendəm/

An additional piece of information added at the end of a document or book

Addenda and addendum both relate to additions, but addenda is the plural form while addendum is singular.
Remember, addenda ends with an a, just like the word extra, which implies more than one.
Use addendum when referring to one single addition or appendix.
Think of addenda as several items being added to a document, whereas addendum is just one.
If youre adding a single note at the end of a book, its an addendum; if youre adding several notes, theyre addenda.