red-root amaranth

indigo, dark blue / indigo-colored dye

(attributive, chemistry) Synonym of シアン化 (shian-ka, “cyanide”)

Synonym of シアン化物 (shian kabutsu, “cyanide”) (chemistry: any compound containing the CN group)

a female given name

(Internet slang, networking) Synonym of ブルートゥース (“Bluetooth”)

(slang) having sex in the open air

blueprint

a red sun, a bright sun, or the summer sun / a day in the traditional Japanese six-day week which is unlucky except for at noon

(idiomatic) a complete stranger