<p><strong>Noun</strong></p><ul><li>A principle or regulation governing conduct, action, procedure, arrangement, etc.: the rules of chess.</li><li>Synonyms: order, dictate, decree, regulation, law, guideline, bylaw, standard, precept.</li><li>The code of regulations observed by a religious order or congregation: the Franciscan rule.</li><li>The customary or normal circumstance, occurrence, manner, practice, quality, etc.: the rule rather than the exception.</li><li>Control, government, or dominion: under the rule of a dictator.</li><li>Synonyms: tyranny, oppression, mastery, domination, regulation, management, government, direction, sway, power, dominion, command, authority.</li><li>Tenure or conduct of reign or office: during the rule of George III.</li><li>A prescribed mathematical method for performing a calculation or solving a problem.</li><li>Ruler (def 2).</li><li>Rule, Astronomy: the constellation Norma.</li><li>Printing: a thin, type-high strip of metal, for printing a solid or decorative line or lines.</li><li>Law: a formal order or direction made by a court, as for governing the procedure of the court general rule or for sending the case before a referee special rule.</li><li>A legal principle.</li><li>A court order in a particular case.</li><li>Rules, Penology: (formerly) a fixed area in the neighborhood of certain prisons within which certain prisoners were allowed to live.</li><li>The freedom of such an area.</li><li>Obsolete: behavior.</li></ul><p><strong>Verb (used with object)</strong></p><ul><li>Ruled, rul·ing: to control or direct; exercise dominating power, authority, or influence over; govern: to rule the empire with severity.</li><li>To decide or declare judicially or authoritatively; decree: The judge ruled that he should be exiled.</li><li>Synonyms: judge, dictate.</li><li>To mark with lines, especially parallel straight lines, with the aid of a ruler or the like: to rule paper.</li><li>To mark out or form (a line) by this method: to rule lines on paper.</li><li>To be superior or preeminent in (a specific field or group); dominate by superiority; hold sway over: For centuries, England ruled the seas.</li></ul><p><strong>Verb (used without object)</strong></p><ul><li>Ruled, rul·ing: to exercise dominating power or influence; predominate.</li><li>To exercise authority, dominion, or sovereignty.</li><li>To make a formal decision or ruling, as on a point at law.</li><li>To be prevalent or current: Higher prices ruled throughout France.</li></ul><p><strong>Verb Phrase</strong></p><ul><li>To prove to be unrelated or not for consideration; eliminate; exclude: to rule out the possibility of error.</li><li>To make impossible or impracticable: The rainstorm ruled out the holiday camping.</li></ul>