principle

principle is a Noun

Definition:

[1] Beginning; commencement. [Obs.] Doubting sad end of principle unsound. Spenser.

[2] A source, or origin; that from which anything proceeds; fundamental substance or energy; primordial substance; ultimate element, or cause.

[3] An original faculty or endowment. Nature in your principles hath set [benignity]. Chaucer. Those active principles whose direct and ultimate object is the communication either of enjoyment or suffering. Stewart.

[4] A fundamental truth; a comprehensive law or doctrine, from which others are derived, or on which others are founded; a general truth; an elementary proposition; a maxim; an axiom; a postulate. Therefore, leaving the principles of the doctrine of Christ, let us go on unto perfection. Heb. vi. 1. A good principle, not rightly understood, may prove as hurtful as a bad. Milton.

[5] A settled rule of action; a governing law of conduct; an opinion or belief which exercises a directing influence on the life and behavior; a rule (usually, a right rule) of conduct consistently directing one`s actions; as, a person of no principle. All kinds of dishonesty destroy our pretenses to an honest principle of mind. Law.

[6] Any original inherent constituent which characterizes a substance, or gives it its essential properties, and which can usually be separated by analysis; -- applied especially to drugs, plant extracts, etc. Cathartine is the bitter, purgative principle of senna. Gregory. Bitter principle, Principle of contradiction, etc. See under Bitter, Contradiction, etc.