rulerrul‧er /ˈrulɚ/ ●●● noun [countable] 
1
someone such as a king who has official power over a country and its peopleTHESAURUSking, queen, prince, princess, monarch, emperor, sovereign► see thesaurus at king2math a flat narrow piece of plastic, wood, or metal that you use for measuring things and drawing straight lines
1 someone such as a king who has official power over a country and its peopleTHESAURUSking, queen, prince, princess, monarch, emperor, sovereign► see thesaurus at king2math a flat narrow piece of plastic, wood, or metal that you use for measuring things and drawing straight lines
