protectorate in Japanese

(UK, historical) Government by a protector; especially, The Protectorate: government of England, Scotland, and Ireland between 1653 and 1659 under the Lord Protector of the Commonwealth Oliver Cromwell, later his son Richard Cromwell.

The authority assumed by a state over another state deemed inferior or dependent, whereby the former protects the latter from invasion and shares in the management of its affairs but the protected state retains its nominal sovereignty.