noun, noun which may take the genitive case particle 'no'
red; vermilion; cinnabar; scarlet
Refers to a bright, slightly orange-tinged red, often associated with traditional Japanese colors, seals, and ink. Can be used as a noun or adjectivally with の.
朱の印鑑を押す。
I stamp a vermilion seal.
彼女は朱の着物を着ていた。
She was wearing a scarlet kimono.