A queen regnant (pl.: queens regnant) is a female monarch, equivalent in rank, title and position to a king. She reigns suo jure (in her own right) over a realm known as a kingdom; as opposed to a queen consort, who is married to a reigning king; or a queen regent, who is the guardian of a child monarch and rules pro tempore in the child's stead or instead of her husband who is absent from the realm, be it de jure in sharing power or de facto in ruling alone. A queen regnant is sometimes called a woman king. A princess, duchess, or grand duchess regnant is a female monarch who reigns suo jure over a principality or (grand) duchy; an empress regnant is a female monarch who reigns suo jure over an empire.
A queen regnant possesses all the powers, such as they may be, of the monarchy, whereas a queen consort or queen regent shares her spouse's or child's rank and titles but does not share the sovereignty of her spouse or child. The husband of a queen regnant traditionally does not share the queen regnant’s rank, title, or sovereignty and usually holds a lower princely title. However, the concept of a king consort is not unheard of in both contemporary and historical periods.
