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dark red; dark brown; reddish brown
翌朝、腕の痣は赤黒かった。
By the next morning the bruise on my arm had turned dark red.
乾いた血の痕は赤黒くて、微かに鉄の匂いがした。
The dried blood stain was dark reddish-brown, faintly smelling of iron.
冬の夕日は湖面に映って、深い赤黒い色を帯びる。
The winter sunset reflected on the lake takes on a deep dark-red hue.