Definition of: rule

(rl) noun
1. Controlling power, or its possession and exercise; government; dominion; authority.
2. A method or principle of action; common or regular course of procedure, or customary standard or form: I make early rising my rule.
3. An authoritative direction or enactment; a concise direction respecting the doing or method of doing something, as one of the regulations of a legislative or deliberative body for the government of its own proceedings, or a regulation to be observed in playing a given game.
4. A regulation for the conduct of religious services or for the government of life; specifically, the body of directions laid down by or for a religious order: the rule of St. Francis.
5. A prescribed form, method, or set of instructions for solving a given class of mathematical problems.
6. An established usage or law, fixing the form or use of words or the construction of sentences: a rule for forming the plural.
7. What belongs to the ordinary course of events or condition of things: In some communities illiteracy is the rule.
8. Regular or proper method; propriety, as of conduct; regularity.
9. Law A formal regulation prescribed by authority touching a certain matter: a rule of court; also, a judicial decision on some motion or special application: a rule to show cause. A rule of court is an order made by a court, and is either general, as for regulating the practice of the court, or special, as an order sending a case before a referee.
10. A straight–edged instrument for use in measuring, or as a guide in drawing lines; a ruler, usually marked in inches, feet, etc.
11. Printing A strip of type–high metal for handling type or for printing a rule or line.
12. A ruled line.
—as a rule Ordinarily; usually.
—v. ruled, rul·ing v.t.
1. To have authority or control over; govern.
2. To influence greatly; dominate: Greed has ruled his life.
3. To decide or determine judicially or authoritatively.
4. To restrain; keep in check: Rule your temper.
5. To mark with straight, parallel lines.
6. To make (such a line) with or as with a ruler.
—v.i.
7. To have authority or control; be in command.
8. To maintain a standard of rates: Prices ruled high.
9. To form and express a decision: The judge ruled on that point.
—to rule out
1. To dismiss from consideration: They ruled out a strike.
2. To preclude; prevent. See synonyms under GOVERN, REGULATE. [<OF reule <L regula ruler, rule <regere lead straight, direct. Doublet of RAIL¹.]
—rul′a·ble adjective Synonyms (noun): canon, formula, guide, maxim, method, order, regulation, standard. See HABIT, LAW, STICK, SYSTEM.