lord protector

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun Title of the regent for the king(dom) of England and/or king(dom) of Scotland.
• noun Title of the head of state of the Commonwealth (republic) which replaced the British monarchy during the parliamentarian supremacy after the execution of the Stuart king, only born by Oliver Cromwell and by his son and designated heir Richard Cromwell, followed by the restoration of the kingdom.
• noun rare English rendering of vidame
• noun English rendering of temporary regent, acting for the absent monarchic head of state.