noun

1. The ruler of an absolute monarchy or the head of state of a constitutional monarchy.

2. The monarch butterfly, Danaus plexippus, and others of genus Danaus, found primarily in North America, so called because of the designs on its wings.

3. (Aboriginal English) A police officer.

Synonyms: Führer, autocrat, autocrator, big man, despot, dictator, potentate, sovereign