Word
principle
Phoneticsprin·ci·ple, stress on the first syllable
US/ˈpɹɪnsəpəɫ/
UK/pɹˈɪnsɪpəl/
Definitions
01moral belief
B2 · Upper Intermediate Countable noun
n. a moral rule or belief that helps you know what is right and influences your behavior.
n. a fundamental truth or proposition that serves as the foundation for a system of belief or behavior or for a chain of reasoning.
“She refused to lie about the accident because it went against her principles.”
“The senator maintained that sticking to his principles was more important than winning the upcoming election through compromise.”
02scientific law
B2 · Upper Intermediate Countable noun Science Academic · Technical
n. a basic law of nature or a rule that explains how a machine or system works.
n. a fundamental law, axiom, or doctrine of nature or science.
“The pilot explained the basic principles of flight to the passengers.”
“Archimedes' principle explains why ships float by calculating the upward force exerted by the displaced water.”
03general rule
B2 · Upper Intermediate Countable noun Academic
n. a general idea or rule that is used as a base for other ideas.
n. a general scientific theorem or law that has numerous special applications across a field.
Español:principio
“In principle, the plan sounds good, but we need to see the costs.”
“While the two parties agree on the proposal in principle, they remain divided on the specific details of implementation.”
04active ingredient
C2 · Proficiency Countable noun Science Technical · Formal
n. a basic substance in a plant or medicine that gives it a special quality.
n. a constituent of a substance, especially one giving it a particular quality or effect.
“Scientists isolated the active principle in the leaf that helps reduce pain.”
“The laboratory succeeded in extracting the bitter principle from the root, allowing for more precise pharmaceutical testing.”
Synonyms
Collocations
Common phrases and expressions where native English speakers use the word “principle” in context.
Verb
01. apply principle
“Students must learn how to apply the principle of physics to real-world problems.”
verb + noun
02. illustrate principle
“The teacher used a simple experiment to illustrate the principle of gravity.”
verb + noun
03. introduce principle
“The first chapter of the textbook aims to introduce the basic principles of economics.”
verb + noun
04. invoke principle
“The lawyer decided to invoke the principle of self-defense during the trial.”
verb + noun
05. outline principle
“The document serves to outline the principles that guide our organization's decisions.”
verb + noun
Adjective
06. ethical principle
“Doctors must follow a strict ethical principle regarding patient confidentiality.”
adj + noun
07. fundamental principle
“Freedom of speech is a fundamental principle of any democratic society.”
adj + noun
08. general principle
“As a general principle, it is better to avoid conflict whenever possible.”
adj + noun
09. scientific principle
“The invention was based on a well-known scientific principle of thermodynamics.”
adj + noun
Noun
10. principle apply
“These legal principles apply to everyone, regardless of their social status.”
noun + verb
Usage
Often used in the plural when referring to a person's moral code; frequently follows the preposition 'in' ('in principle') to indicate theoretical agreement.
Pitfall
the school principal
the school principle
Learners often confuse 'principle' (a rule) with 'principal' (the head of a school or the most important thing).
Confusables
Principal is an adjective meaning main or a noun for a leader, while principle is always a noun meaning a fundamental rule or belief.
RememberThe Principal is your pal; a principle is a rule.
Real-World Examples
“While Guardiola had principles he stuck to throughout his career, he did not stick to one system.” “Bouke Klein Teeselink, an academic at King’s College London and an expert on the impact of AI on work, said the boot camp was a “good idea in principle”.” “These questions go beyond the limits of astronomy; they can’t be answered, even in principle, by developing more sensitive telescopes.” “Eckhard Jann points out that the current system is still largely founded on principles set out in 1944.” Word family
NOUN
ADJECTIVE
Related words
Idioms
Domain
- Exam level
- CambridgeCambridgeCambridge English QualificationsThe exam suite from Cambridge University Press & Assessment, from A1 Movers up to C2 Proficiency. The benchmark names double as CEFR labels.B2 FirstIELTSIELTSInternational English Language Testing SystemThe 0–9 band test co-owned by the British Council, IDP, and Cambridge. Used for university entry, work, and migration.5.5–6.5TOEFL iBTTOEFL iBTTest of English as a Foreign Language, Internet-Based TestETS's academic English test, the standard route for US university admissions. Scored 0–120, with a 1–6 scale since 2026.1–6 scale: 4.0–4.572–94TOEICTOEICTest of English for International CommunicationETS's workplace English test, big in Japan and Korea. Listening & Reading scores 10–990 and tops out at C1.785–944
- Frequency
- Common
- Level
- B2 · Upper IntermediateOxford
- Updated
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QR code
englishreference.com/q/principle
Traducciones: Kaikki.org (Wiktionary), CC BY-SA 4.0