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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
herein defined
Grammar usage guide and real-world examplesTable 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
30 human-written examples
Such a passage is herein defined as an OntoPassage.
These kinds of enhancement are, herein, defined to be events of Class 1 and Class 2 respectively.
Science
It is hereby declared that filled milk, as herein defined, is an adulterated article of food, injurious to the public health, and its sale constitutes a fraud upon the public.
Academia
Prefrontal cortex (PFC) is implicated in executive control, herein defined as the ability to map external inputs and internal goals toward actions that solve problems or elicit rewards.
Stiffening configuration is herein defined as a design variable that indicates the combination of axial, transverse and diagonal stiffeners in the stiffened panel.
Science
Notwithstanding any other provision of law, whenever the Board of Directors shall determine that an insured depository institution is not engaged in the business of receiving deposits, other than trust funds as herein defined, the Corporation shall notify the depository institution that its insured status will terminate at the expiration of the first full assessment period following such notice.
Academia
Human-verified similar examples from authoritative sources
Similar Expressions
30 human-written examples
First, based on the above concepts, we herein define three statistical and temporal measures that exhibit distinct properties under admissible and malicious operations for latter authenticity judgment.
We herein define the probability of a given mRNA being bound to a ribosome as translational efficiency, since protein production is proportional to the number of bound ribosomes [ 23].
Science
Technology herein is defined broadly to include intellectual property.
Herein we defined the adjuvanticity of a novel lecithin-based nanoparticle engineered from emulsions.
Herein, we defined positively selected codons as those having a cumulative probability >0.80 of γ ≥ 1.
Science
Expert writing Tips
Best practice
Place the phrase in parentheses immediately after introducing a term to provide an instant, restrictive definition without interrupting the flow of the sentence.
Common error
Do not use "herein defined" if the definition actually resides in an external document or a different chapter not covered by the current text's scope. In such cases, use "defined in" followed by the specific reference.
Source & Trust
91%
Authority and reliability
4.9/5
Expert rating
Real-world application tested
Linguistic Context
The phrase "herein defined" functions as an adverbial modifier or part of a participial phrase that restricts the semantic scope of a noun. According to Ludwig, it is frequently used to introduce an operational definition that holds true only within the specific text at hand. It creates a closed linguistic system where the author can assign specific values to terms regardless of their general dictionary definitions.
Frequent in
Science
65%
Academia
25%
Formal & Business
10%
Less common in
News & Media
2%
Wiki
1%
Social Media
0.1%
Ludwig's WRAP-UP
In summary, "herein defined" is a powerful linguistic anchor used to ground definitions within a specific text. Data from Ludwig shows that it is a staple of formal, scientific and legal writing, where clarity is paramount. While it may feel archaic in modern casual prose, its utility in professional documents remains unchallenged. Whether you are defining a biological mutant in a lab report or a 'party' in a legal contract, using "herein defined" ensures that your reader understands exactly what you mean—and where that meaning applies. For a more modern feel, you might consider "defined here", but for maximum authority, the traditional phrase remains the preferred choice among experts.
More alternative expressions(10)
Phrases that express similar concepts, ordered by semantic similarity:
defined herein
Inverts the order to place the emphasis on the definition itself rather than the location.
hereinafter defined
Specifically indicates that the definition applies to all subsequent mentions in the text.
as used herein
Focuses on the functional application of the term within the document.
as defined in this context
More modern and accessible version that avoids the archaic 'herein'.
specified here
Simpler and less formal alternative suitable for technical manuals.
designated herein
Common in legal contexts to assign a specific label to a concept.
referred to herein
Used when the phrase refers to an existing term rather than establishing a new definition.
defined in this document
Replaces the adverb with a clear prepositional phrase for transparency.
herein described
Slightly broader as it suggests a description rather than a strict logical definition.
hereby defined
Implies that the act of defining is happening exactly at this moment in the text.
FAQs
What is the meaning of "herein defined"?
The phrase "herein defined" means that a specific term is being given a particular meaning within the document or section currently being read. It is a formal way to establish clarity and prevent ambiguity. You can also use "defined herein" or "as used in this document" for similar results.
Is "herein defined" too formal for business emails?
Yes, it is often considered too stiff for general correspondence. Unless you are writing a contract or a formal policy, it is better to use "defined below" or simply explain the term directly.
Where should I place "herein defined" in a sentence?
It is most effective when used as a parenthetical appositive. For example: "The primary objective (herein defined as the project's main goal) must be met by Friday." Alternatively, it can function as a predicate: "In this study, success is "herein defined as" a 20% increase in yield."
What is the difference between "herein defined" and "hereinafter defined"?
While "herein defined" refers to the definition provided in this document generally, "hereinafter defined" explicitly signals that the definition applies to all future mentions of the term from this point forward in the text.
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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
91%
Authority and reliability
4.9/5
Expert rating
Real-world application tested