Used and loved by millions
Since I tried Ludwig back in 2017, I have been constantly using it in both editing and translation. Ever since, I suggest it to my translators at ProSciEditing.

Justyna Jupowicz-Kozak
CEO of Professional Science Editing for Scientists @ prosciediting.com
in addendum
Grammar usage guide and real-world examplesUSAGE SUMMARY
"in addendum" is a correct and usable phrase in written English.
It is typically used in formal or legal writing to indicate that something is being added to a previous statement or document. Example: "In the addendum to my contract, I have included the updated terms and conditions for the project."
✓ Grammatically correct
Science
News & Media
Academia
Table of contents
Usage summary
Human-verified examples
Expert writing tips
Linguistic context
Ludwig's wrap-up
Alternative expressions
FAQs
Human-verified examples from authoritative sources
Exact Expressions
7 human-written examples
The NNL Program suffered a setback beginning in 1989 when it was perceived as a threat by some private landowner rights organizations and that account is found in Addendum.
Science
In addendum 1 the motivation items are presented.
Science
Multiple cases exist in nature of the use of a haploid state by otherwise diploid eukaryotes, and in addendum 2, I have developed three such examples that I find particularly eloquent i.e. the cases of organisms that go through haploid stages, of the sexual chromosomes and of the endosymbiotic organelles.
Science
As developed in addendum 2, the haplodiploid mode of reproduction of insects such as the hymenoptera (ants, bees, wasps...) corresponds to a very effective way of eliminating recessive mutations, and it is quite remarkable that the hymenoptera represent more than 30% of all insect species.
Science
(and also see note 10 in addendum 4 about the fact that many of these predictions were actually supported by many papers that were already published, but which I discovered only after I had described the model) This article/review/Hypothesis represents a great amount of work.
Science
This has now been published in four volumes (JECFA Monographs 1, 2005 and 2006) to replace the earlier edition and it incorporates all the additions and revisions made since 1992, up to and including those contained in Addendum 13, published in 2005.
Human-verified similar examples from authoritative sources
Similar Expressions
53 human-written examples
The Enbridge spill is only mentioned briefly in addendums.
News & Media
Underneath was a tongue-in-cheek addendum.
News & Media
In an addendum to the article in the magazine, the Sunday Times confirmed that since finishing the piece, Gill had started taking the drug, known as Nivolumab.
News & Media
In a written addendum in the Congressional Record, Mr. Hare said the bill would also create high-paying jobs.
News & Media
The genetic identification, brief clinical history and radiologic appearance of the patient carrying the heterozygous ACTA2 mutation resulting in the R179H change was described in the addendum [ 12] and as patient 6 [ 10], 4 years before she expired.
Expert writing Tips
Best practice
When using "in addendum", ensure the original document is clearly identified so readers can easily connect the added information to its source.
Common error
Avoid using "in addendum" when simply referring to an appendix or general supplementary material. "Addendum" specifically implies an addition or correction made after the original document was finalized.
Source & Trust
85%
Authority and reliability
4.5/5
Expert rating
Real-world application tested
Linguistic Context
The phrase "in addendum" primarily functions as a prepositional phrase. As supported by Ludwig, it modifies a verb or noun, indicating where additional information or modifications can be found. It's used to direct the reader to supplementary content added after the main text.
Frequent in
Science
42%
News & Media
33%
Academia
25%
Less common in
Formal & Business
0%
Encyclopedias
0%
Wiki
0%
Ludwig's WRAP-UP
In summary, "in addendum" serves as a formal prepositional phrase directing readers to supplementary information. Ludwig AI confirms its grammatical correctness and suitability for formal and scientific contexts. While not as common as other phrases, its usage is consistent across science, news, and academic sources. The phrase indicates updates or corrections to a primary document, distinguishing it from general supplementary materials found in appendices. Therefore, understanding its specific meaning and appropriate context is crucial for effective communication in formal writing.
More alternative expressions(6)
Phrases that express similar concepts, ordered by semantic similarity:
in the addenda
Plural form, referring to multiple additions or supplements.
as an appendix
Refers to supplementary material placed at the end of a document.
as a supplement
Focuses on the supplemental nature of the added information.
in a supplementary note
Specifies that the information is presented as a separate note providing further detail.
in addition
Highlights the act of adding more information without specifying its location in a separate section.
in an attached note
Emphasizes the physical attachment of the additional information.
in the postscript
Indicates an addition made after the main body of a text, typically a letter.
as a follow-up
Highlights that the information is provided to expand on something previously mentioned.
by way of a rider
Implies an attachment or amendment to a document, often a legal one.
as a codicil
Refers to a legal document that adds to or changes a will.
FAQs
How do you use "in addendum" in a sentence?
The phrase "in addendum" is used to indicate that additional information or corrections are included as a supplement to a main document. For example, "In the addendum to the report, we included updated financial projections."
What's the difference between "in addendum" and "in the appendix"?
"In addendum" refers to additions or changes made after a document's completion, while "in the appendix" refers to supplementary material included at the end of a document from the start. If you are looking for a similar phrasings, consider using "as an appendix".
What can I say instead of "in addendum"?
You can use alternatives like "as a supplement", "in addition", or "as an appendix" depending on the context.
Is it correct to say "in addenda" instead of "in addendum"?
"In addenda" is the plural form, used when referring to multiple addendums. "In addendum" is singular and refers to a single addition or supplement.
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Table of contents
Usage summary
Human-verified examples
Expert writing tips
Linguistic context
Ludwig's wrap-up
Alternative expressions
FAQs
Source & Trust
85%
Authority and reliability
4.5/5
Expert rating
Real-world application tested