a red fox (Vulpes vulpes)

a large Japanese field mouse

red line / (historical) Short for 赤線地帯(あかせんちたい) (akasenchitai): Akasen (districts in Japan where prostitution and the sex industry flourished)

red brick

Synonym of ドール (dōru, “dhole”)

"red sheet", specifically a red translucent plastic sheet used in studying to render red-colored text illegible

failing grade

Alternative spelling of 赤ずきん

a red deer

a red panda