"Male heirs first" is male-preference primogeniture, the system still holding in Britain and Spain but replaced in Belgium, Denmark, the Netherlands, Norway and Sweden by cognatic primogeniture. Under which system no one in the whole history of the world has ever yet succeeded, it is brand new, but the next change of reign in Sweden will see it happen.
Semi-salic law is a variant on full Salic, which means agnatic (male-to-male) succession only. Semi-salic law provides either that in the event of the complete exhaustion of the male line the nearest female relative of the last male succeeds, or the nearest male relative through a female of the last male succeeds.
Semi-salic law is a variant on full Salic, which means agnatic (male-to-male) succession only. Semi-salic law provides either that in the event of the complete exhaustion of the male line the nearest female relative of the last male succeeds, or the nearest male relative through a female of the last male succeeds.