noun
Rikkokushi; six national histories
Refers collectively to the six official national histories compiled in the Nara and Heian periods. Often used in historical contexts.
See also: 六国史
日本紀は、奈良時代から平安時代にかけて編纂された六つの国史の総称です。
Nihongi is a general term for the six national histories compiled from the Nara to Heian periods.
noun
Nihon Shoki; Chronicles of Japan
Specifically the second oldest work of Japanese history, completed in 720 CE. Also known as Nihongi.
See also: 日本書紀
日本紀は720年に完成した日本で二番目に古い歴史書です。
The Nihon Shoki is the second oldest history book in Japan, completed in 720.
六国史 is the standard term for the six national histories; 日本紀 can refer to the whole set or specifically to the Nihon Shoki.
From 日本 (Nihon, 'Japan') + 紀 (ki, 'chronicle'). The exact historical derivation of the reading にほんぎ is uncertain.