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red; crimson; scarlet
red-containing colour (e.g. brown, pink, orange)
red light (traffic)
red ink (i.e. in finance or proof-reading); (in) the red
complete; total; perfect; obvious
Red (i.e. communist)
copper
red 5-point card
「朱」 has other readings with different meanings.
朱い花が咲いている。
Red flowers are blooming.
夕焼けで空が朱く染まっている。
The sky is dyed red by the sunset.
秋になると山全体が朱く色づいてとても美しい。
In autumn, the entire mountain turns red and is very beautiful.