was the highest rank in the prewar Imperial Japanese Navy. The term gensui was used for both the Navy and the Imperial Japanese Army, and was a largely honorific title awarded for extremely meritorious service to the Emperor. In the Meiji period, the title was awarded to five generals and three admirals. In the Taisho period it was awarded to six generals and six admirals, and in the Showa period it was awarded to six generals and four admirals. Equivalent to a five-star rank (OF-10), it is similar to Admiral of the Fleet in the UK Royal Navy and Fleet Admiral in the United States Navy.