Main Entry: rul·er

Pronunciation: \ˈrü-lər\

Function: noun

Date: 14th century

1 : one that rules; specifically : sovereign
2 : a worker or a machine that rules paper
3 : a smooth-edged strip (as of wood or metal) that is usually marked off in units (as inches) and is used as a straightedge or for measuring

— rul·er·ship \-ˌship\ noun