Tag Archives: difference between appendix and appendum

Appendix, addendum, annexure and attachment

By Mary Morel

Appendix and addendum

Reader’s question: What’s the difference between an appendix and an addendum?

Can they be used interchangeably or should we be using one over the other in specific circumstances?

Answer: My first reaction was that these terms are not interchangeable, but when I looked in a dictionary, I was surprised to find that one definition of an addendum was ‘an appendix’. Another definition was ‘an addition’, and that’s how I regard an addendum.

Being truly pedantic, I would distinguish between these words as follows:

An appendix supplements the body of a document, providing detailed information that not everyone will want to read. Appendices are often statistical, historical or technical.

An addendum is extra information that the writer discovered after writing the report, such as a new study on the topic. It’s a bit like a PS.

These words both have two possible plurals:

appendices or appendixes

addenda or addendums

Which plural would you use?

Annexure and attachment

I am writing an addendum to this original post.

Since responding to the original question, I have seen the words annexure and attachment used in board papers to describe appendices. However, I haven’t seen addendum in the board paper world. (The Macquarie Dictionary recognised annex, but not annexure.)

What terms to you use and why?

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