Ninigi-no-Mikoto vs Ninigi

Ninigi-no-Mikoto and Ninigi both are nouns.

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

As nouns, Ninigi-no-Mikoto and Ninigi are synonyms defined as:

Ninigi-no-Mikoto and Ninigi: grandson of Amaterasu and first ruler of Japan

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

Ninigi-no-Mikoto (noun)	Ninigi (noun)
grandson of Amaterasu and first ruler of Japan	grandson of Amaterasu and first ruler of Japan