Definition of principle
1a
: a comprehensive and fundamental law, doctrine, or assumption
b(1)
: a rule or code of conduct
(2)
: habitual devotion to right principles
a man of principle
c
: the laws or facts of nature underlying the working of an artificial device
2
: a primary source : origin
b
: an ingredient (such as a chemical) that exhibits or imparts a characteristic quality
in principle
: with respect to fundamentals
prepared to accept the proposition in principle
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Merriam-Webster unabridged
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Time Traveler for principle
The first known use of principle was in the 14th century
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