n.
Pronunciation: ' rü-l ə r
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 \ - ˌ ship \ noun