What is "aleamotua"

Aleamotua (birth date unknown, died 18 November 1845) (addressed as Tupou when he became Tu'i Kanokupolu, then baptized as Siosaia (Josiah) Tupou and later known as Tupou ‘i Fale Tui Papai, after the name of the area in which he was buried). Aleamotua was the 18th Tu'i Kanokupolu of Tonga, the third lineage of Tongan Kings with the political and military power who ruled in support of the Tu'i Tonga (The Sacred King of Tonga).