Regent

adj. pertaining to one who rules a nation in the King's absence

n. one who governs a state in the king's absence; member of a management board, member of a board of governors

A Regent, from the Latin regens "who reigns" , is a person selected to act as Head of state (ruling or not) because the ruler is a minor, not present or debilitated. Thus, the common use is for an acting deputy governor. The Oxford English Dictionary defines the term as "A person appointed to administer a State because the Monarch is a minor, is absent or is incapacitated."
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Noun
1. members of a governing board
(synonym) trustee
(hypernym) committee member
(member-holonym) governing board
2. someone who rules during the absence or incapacity or minority of the country's monarch
(hypernym) ruler, swayer
(hyponym) Catherine de Medicis
Adjective
1. acting or functioning as a regent or ruler; "prince-regent"
(synonym) regent(ip)
(similar) powerful
(classification) combining form

n. regent, one who governs a state in the king's absence

n. regent, one who governs a state in the king's absence; member of a management board, member of a board of governors