A vibrant pale greenish-blue colour between blue and green in the visible spectrum; the complementary colour of red; the colour obtained by subtracting red from white light.

Of the colour cyan.

Alternative form of cyano-

plural of cyan

(chemistry) Of cyanogen or its derivatives / azure-blue / (botany, of a flower) Containing an anthocyanin

(chemistry, countable) Any compound containing the -C≡N group or the CN⁻ anion. / (uncountable) Sodium or potassium cyanide, used in the extraction of gold and silver or as a poison.

(transitive) To treat or poison with cyanide.

Alternative form of cyanine

Any of a family of synthetic polymethine blue dyes used in photography etc.

(metallurgy) The extraction of gold or silver from their ores using the cyanide process