ETYM Latin, from addere to add.
(Irregular plural: addenda).
Textual matter that is added onto a publication; usually at the end; SYN. supplement, postscript.
Something added; appendix.
(Latin) Something to be added, usually in writing, which qualifies a foregoing thesis or statement.
Ajout (ŕ un texte).
1. Complément. Le supplément littéraire d'un journal.
2. Rallonge.
3. Extra. Payer un supplément.