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addendum

[ uh-den-duh m ]
/ əˈdɛn dəm /
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noun, plural ad·den·da [uh-den-duh] /əˈdɛn də/ for 1, 2; ad·den·dums for 3.

a thing to be added; an addition.
an appendix to a book.
Machinery.
  1. the radial distance between the tip of a gear tooth and the pitch circle of a gear or the pitch line of a rack.Compare dedendum.
  2. Also called addendum circle.an imaginary circle touching the tips of the teeth on a gear.

RELATED WORDS

postscript, appendix, codicil, extension, extra, addition, adjunct, supplement, augmentation, attachment, appendage, rider

Nearby words

  1. added sixth,
  2. added title page,
  3. added-value tax,
  4. addend,
  5. addenda,
  6. adder,
  7. adder's-meat,
  8. adder's-mouth,
  9. adder's-tongue,
  10. adderall

Origin of addendum

1785–95; neuter singular of Latin addendus to be added, gerundive of addere to add
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for addendum

British Dictionary definitions for addendum

addendum

/ (əˈdɛndəm) /

noun plural -da (-də)

something added; an addition
a supplement or appendix to a book, magazine, etc
the radial distance between the major and pitch cylinders of an external screw thread
the radial distance between the pitch circle and tip of a gear tooth

Word Origin for addendum

C18: from Latin, literally: a thing to be added, neuter gerundive of addere to add
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Word Origin and History for addendum

addendum

n.

1794, literally "something added," from Latin addendum, neuter of addendus "that which is to be added," gerundive of addere (see add (v.)). Classical plural form is addenda.

Online Etymology Dictionary, © 2010 Douglas Harper