Ninigino-mikoto is a Japanese word that refers to a deity in Shinto mythology. As with many complex ideas and concepts, there are multiple words that can be used as synonyms for this term. Some possible synonyms for ninigino-mikoto might include Amatsu Mikaboshi, Okami, or even just kami in general. Each of these words refers to a divine or spiritual force, often associated with the natural world. Other possible synonyms might include deities such as Izanagi, Izanami, or even Amaterasu, who all play important roles in Shinto mythology and are often associated with the power of creation and regeneration. Overall, there are many different words that could be used as synonyms for ninigino-mikoto, depending on the specific context and the intended meaning.