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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
「紅」 has other readings with different meanings.
紅い花が咲いている。
Red flowers are blooming.
信号が赤だから止まってね。
The light is red, so stop.
秋になると葉が紅く色づく。
In autumn, the leaves turn red.