The wife of a reigning king is called a queen consort. The husband of a reigning queen is usually not called "king consort", although it was more common in Europe’s past for husbands of queens regnant to become reigning kings (e.g., Philip II of Spain in England, Antoine of Bourbon-Vendôme in Navarre, Ferdinand of Saxe-Coburg-Gotha in Portugal, etc.) or indeed kings consort (Francis of Spain). He is normally called a prince consort.
Where some title other than that of king is held by the sovereign, his wife is referred to by the feminine equivalent, such as princess consort or empress consort.
In monarchies where polygamy has been (such as Morocco, Thailand) or is still practiced (such as the Zulu nation and the various Yoruba polities), the number of wives of the king varies. In Morocco, the present king Mohammed VI has broken with tradition and given his wife, Lalla Salma, the title of princess. Prior to the reign of King Mohammed VI, the Moroccan monarchy had no such title. In Thailand the queen and king must be of royal blood. The king's other consorts are accorded royal titles that confer status. Other cultures maintain different traditions on queenly status. A Zulu chieftain designates one of his wives "Great Wife", which would be the equivalent to queen consort. Conversely, in Yorubaland, all of a chief's princesses consort are essentially of equal rank. Although one of their number, usually the one that has been married to the chief for the longest period of time, may be given a chieftaincy of her own to highlight her relatively higher status when compared to the other wives, she does not share her husband's ritual power as a chieftain. When a woman is to be vested with an authority similar to that of the chief, she is usually a lady courtier in his service who is not married to him but who is expected to lead his female subjects on his behalf.
