[əˈdɛndəm], (Noun)

Definitions:
- an item of additional material added at the end of a book or document, typically in order to correct, clarify, or supplement something
(e.g: the group has issued an addendum to the letter)

- the radial distance from the pitch circle of a cogwheel or wormwheel to the crests of the teeth or ridges


Phrases:

Origin:
late 17th century: Latin, ‘that which is to be added’, gerundive of addere (see add)