Ninigino-Mikoto vs Ninigi

Ninigino-Mikoto and Ninigi both are nouns.

Word	Noun	Adjective	Verb	Adverb
Ninigino-Mikoto	Yes	No	No	No
Ninigi	Yes	No	No	No

As nouns, Ninigino-Mikoto and Ninigi are synonyms defined as:

Ninigino-Mikoto and Ninigi: grandson of Amaterasu and first ruler of Japan

Other synonyms of Ninigino-Mikoto include Ninigi-no-Mikoto.

Ninigino-Mikoto (noun)	Ninigi (noun)
grandson of Amaterasu and first ruler of Japan	grandson of Amaterasu and first ruler of Japan