Nanako most commonly means "seventh child," in Japanese.
Although there are also some variations to Nanako which is a Japanese female name which include "green/vegetable child," or even "red apple child.
The meaning of the name and word Nanako also depends on the kanji characters that are used.
But the name and word Nanako in Japanese most commonly and generally signifies nature, innocence or a desired birth
Nanako in Japanese can also refer to a Japanese metalworking technique that is also known as the fish-roe pattern.
Or Nanako in Japanese can also be a nickname, like seen with anime characters.
The name Nanako in Japanese is a combination of two elements, which include nana, which means red, and ko, which translates to and means child.
Common meanings of Nanako are seventh child when combining Nana, (Seven) and the word ko, which means child.
Red Apple Child when you combine Nana, which is red, and Ko, which is child.
Green/vegetable Child is when you use the Kanji for vegetable which is (菜).
Other meanings and uses of Nanako include Literary and Anime, such as a name for characters like Nanako Dojima in Persona 4, or a spirit in Fate/stay night, which references "Seven".
Nanako when referring to metalwork is a textured pattern that resembles fish roe or (魚子) when used on sword fittings.
The name Nanako in Japanese evokes themes of innocence, youth, and nature in Japanese culture and often is associated with the Shichi-Go-San festival which celebrates ages 3, 5, and 7.