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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
cold-blooded
Grammar usage guide and real-world examplesUSAGE SUMMARY
The word "cold-blooded" is correct and can be used in written English.
It is most commonly used to describe someone who is seen as unfeeling or indifferent, or to describe an animal that is ectothermic, relying on external sources of heat to regulate its body temperature. Example sentence: In the boardroom negotiations, he remained cold-blooded and unmoved by his opponents' pleas.
✓ Grammatically correct
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
57 human-written examples
"Cold-blooded mur-dah!
News & Media
It's cold-blooded realpolitik.
News & Media
Cold-blooded, and probably correct.
News & Media
Both are cold-blooded.
News & Media
"He is cold-blooded.
News & Media
"Not cold-blooded killers.
News & Media
Cold-blooded killings.
News & Media
Who said vampires were cold-blooded?
News & Media
Human-verified similar examples from authoritative sources
Similar Expressions
3 human-written examples
COLD BLOODED, by Lisa Jackson.
News & Media
It is horribly cold blooded and cruel.
News & Media
11 1 COLD BLOODED, by Lisa Jackson.
News & Media
Expert writing Tips
Best practice
In scientific contexts, "cold-blooded" is often replaced by the more precise term "ectothermic" to avoid negative connotations.
Common error
Avoid using "cold-blooded" when you simply mean someone is calm or composed under pressure. "Cold-blooded" implies a lack of empathy or ruthlessness, not just composure.
Source & Trust
90%
Authority and reliability
4.5/5
Expert rating
Real-world application tested
Linguistic Context
The phrase "cold-blooded" functions primarily as an adjective, modifying nouns to describe a quality or characteristic. Ludwig showcases its use in describing both animal physiology and human behavior, typically denoting a lack of emotion or ruthlessness.
Frequent in
News & Media
75%
Academia
15%
Science
10%
Less common in
Encyclopedias
0%
Wiki
0%
Formal & Business
0%
Ludwig's WRAP-UP
In summary, "cold-blooded" is a versatile adjective primarily used to describe a lack of empathy or ruthlessness in humans or to classify animals that regulate body temperature externally. As confirmed by Ludwig, the phrase is grammatically correct and frequently appears in news, academic, and scientific contexts. While seemingly straightforward, misuse can lead to misinterpretations or melodramatic writing. Understanding its dual meaning and the negative connotation is key to employing it effectively. Remember, while Ludwig confirms its validity, context is crucial for accurate and impactful communication.
More alternative expressions(6)
Phrases that express similar concepts, ordered by semantic similarity:
unemotional
Emphasizes the lack of emotion or feeling.
unfeeling
Similar to unemotional, but with a stronger connotation of indifference.
callous
Highlights the insensitivity and disregard for others' feelings.
heartless
Focuses on the absence of compassion or empathy.
without remorse
Signifies the lack of regret or guilt.
ruthless
Implies a determination to achieve goals without concern for the consequences.
calculating
Highlights the planning and scheming nature of an action
detached
Describes a state of being aloof and uninvolved.
clinical
Suggests a detached, analytical perspective, often lacking empathy.
ectothermic
Scientifically accurate term relating to the regulation of body temperature
FAQs
How can I use "cold-blooded" in a sentence?
You can use "cold-blooded" to describe a lack of feeling or mercy, as in "The crime was a "cold-blooded murder"". It can also refer to animals that regulate their body temperature externally.
What does it mean to describe someone as "cold-blooded"?
Calling someone "cold-blooded" suggests they are ruthless, unemotional, and capable of cruel actions. It implies a lack of empathy or remorse.
Is "cold-blooded" the same as "calm" or "collected"?
No, while a "cold-blooded" person might appear calm, the term implies a deeper lack of feeling and a willingness to act ruthlessly. Being calm is about composure, while being "cold-blooded" is about a lack of empathy.
Are there scientific uses of the term "cold-blooded"?
Yes, in biology, "cold-blooded" (more accurately termed ectothermic) refers to animals that regulate their body temperature through external means, such as reptiles and amphibians.
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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
90%
Authority and reliability
4.5/5
Expert rating
Real-world application tested