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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
is defined as
Grammar usage guide and real-world examplesUSAGE SUMMARY
The phrase "is defined as" is correct and usable in written English.
You can use this phrase to introduce a definition or explanation of something. For example, "Integrity is defined as the quality of being honest and having strong moral principles."
✓ Grammatically correct
Science
News & Media
Encyclopedias
Alternative expressions(20)
is referred to as as
is equivalent to
is mandated as
is examined as
becomes defined as
is correctly stated as
can also mean
is labeled as
should be interpreted as
can be altered as
can be taken to mean
is interpreted as
suggests
is characterized as
is termed as
is specified as
signifies
can be illustrated as
is characterised as
is outlined as
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
59 human-written examples
The mapping is defined as,.
which is defined as (1.15).
MCC is defined as below.
Science
Q: What is defined as off-topic?
News & Media
His role is defined as a "trequartista".
News & Media
Such a cryptosystem is defined as "perfect".
Encyclopedias
A second-order difference is defined as.
Encyclopedias
The fidelity is defined as.
Science & Research
The problem is defined as "nothing-buttery".
News & Media
What is defined as off-topic?
News & Media
Pre-term is defined as <37 weeks52.
Science & Research
Expert writing Tips
Best practice
When defining a term, ensure your definition is clear, concise and uses language appropriate for your target audience.
Common error
Avoid defining a term using the term itself or closely related words. This creates a circular definition that provides no new information.
Source & Trust
82%
Authority and reliability
4.5/5
Expert rating
Real-world application tested
Linguistic Context
The phrase "is defined as" functions as a linking verb introducing a definition or explanation. It connects a subject with its definition, as seen in Ludwig's examples where various terms are precisely defined across different fields.
Frequent in
Science
45%
News & Media
25%
Encyclopedias
10%
Less common in
Academia
8%
Wiki
6%
Formal & Business
6%
Ludwig's WRAP-UP
The phrase "is defined as" is a versatile and commonly used expression for introducing definitions or explanations. Grammatically correct and appropriate for various contexts, it's particularly prevalent in scientific and technical writing, according to Ludwig. While alternatives like "is characterized as" or "is understood to be" offer subtle nuances, "is defined as" remains a clear and direct way to establish the meaning of a term, as validated by Ludwig AI. Remember to avoid circular definitions and tailor your language to your audience.
More alternative expressions(6)
Phrases that express similar concepts, ordered by semantic similarity:
is characterized as
Focuses on describing the key attributes or qualities, rather than a strict definition.
is understood to be
Emphasizes the common interpretation or generally accepted meaning.
can be described as
Offers a way to portray something's attributes or nature using descriptive words.
is interpreted as
Highlights the act of assigning meaning or understanding.
is known as
Highlights common knowledge of a term or concept.
is considered to be
Focuses on a consensus of opinion rather than a strict definition.
is referred to as
Highlights the act of naming or labeling.
is expressed as
Focuses on how something is represented, often mathematically or symbolically.
is equivalent to
Highlights the equivalence or interchangeability of two things.
is designated as
Focuses on assigning a specific role or function.
FAQs
How do I use "is defined as" in a sentence?
Use "is defined as" to introduce a formal definition of a term or concept. For example, "Integrity is defined as the quality of being honest and having strong moral principles."
What are some alternatives to "is defined as"?
You can use alternatives such as "is characterized as", "is understood to be", or "can be described as" depending on the context.
Is it better to use "is defined as" or "means" when providing a definition?
"Is defined as" is generally more formal and precise, suitable for academic or technical writing. "Means" is more informal and can be used in broader contexts.
When should I avoid using "is defined as"?
Avoid using "is defined as" when the meaning is already clear from the context or when providing an informal explanation rather than a strict definition.
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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
82%
Authority and reliability
4.5/5
Expert rating
Real-world application tested