皇室典範では、天皇の三世以下の男子を王と定めている。
The Imperial House Law designates male descendants of the Emperor from the third generation onward as princes.
親王の子は王と称された。
The son of an imperial prince was styled a prince.
戦前の宮家には王の称号を持つ皇族が多くいた。
In the prewar collateral houses there were many imperial family members who held the title of prince.