n.
Pronunciation: ə - ' den-d ə m
Function: noun
Inflected Form: plural -den · da \ - ' den-d ə \ also -den · dums
Etymology: Latin, neuter of addendus, gerundive of addere
Date: 1684
1 : a thing added : ADDITION
2 : a supplement to a book ― often used in plural but singular in construction