principle
UK: ˈprɪnsəpəl | US: ˈprɪnsəpəl
n. a fundamental truth or proposition serving as the foundation for belief or action
n. a moral rule or belief governing personal behavior
n. a general scientific theorem or natural law
Derived from Latin principium ("beginning, foundation"), via Old French principe. The root princip- comes from primus ("first") + capere ("to take"), reflecting the idea of "primary source" or "foundational rule." Over time, it evolved to emphasize abstract truths (e.g., moral/scientific principles) rather than literal beginnings. The spelling stabilized in Middle English, retaining the Latin-origin princip- core.
Honesty is a key principle of ethical leadership.
The device operates on the principle of electromagnetic induction.
She refused to compromise her principles.
Newton's laws are fundamental principles of physics.
The school teaches students to uphold democratic principles.