• Addendum

    Origin

    From the gerundive of Latin addere ("to add").

    Noun

    addendum

    (plural addenda or addendums)
    1. Something to be added; especially text added as an appendix or supplement to a document.
    2. A postscript.
    3. (engineering) The height by which the tooth of a gear projects beyond (outside for external, or inside for internal) the standard pitch circle or pitch line.
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