addenda addend • addendum · · · Info · Definitions · Synonyms · Characters · · addenda · · Text Latin · · Script 7 · · Length Definitions · · · (noun) textual matter that is added onto a publication; usually at the end. Synonyms: addendum, supplement, postscript. · · Noun Definition 1 Synonyms · · · addendum · · Synonym 1 supplement · · Synonym 2 postscript · · Synonym 3 Characters · · a latin small letter a U+0061 d latin small letter d U+0064 e latin small letter e U+0065 n latin small letter n U+006E