addendum

/əˈdɛndəm/

/əˈdɛndəm/

Other forms: addenda; addendums

When you make an addendum to a document, you are adding text to the end. Addenda tend to be serious business as they're added to contracts, reports, and studies.

There is nothing dumb about an addendum; often an addendum makes a document "smarter" by adding more information. If you did a science report on plant growth and found that after your study was complete, the plant flowered in an unusual way, you might describe that as an addendum to your report. Fun fact: the plural of addendum is addenda.

Definitions of addendum

1. noun

   textual matter that is added onto a publication; usually at the end
   synonyms: postscript, supplement

   types:

   appendix

   supplementary material that is collected and appended at the back of a book

   continuation, sequel

   a part added to a book or play that continues and extends it

   shirttail

   a brief addendum at the end of a newspaper article

   codicil

   a supplement to a will; a testamentary instrument intended to alter an already executed will

   type of:

   matter

   written works (especially in books or magazines)
2. noun

   a thing that is added or will be added
   type of:

   add-on, addition, improver

   a component that is added to something to improve it