monarch

ot 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.
4. (often capitalised) A stag which has sixteen or more points or tines on its antlers.