indigo blue

noun
1.
indigo (def 4).
2.
Also called indigo, indigotin. a dark-blue, water-insoluble, crystalline powder, C 16 H 10 N 2 O 2 , having a bronzelike luster, the essential coloring principle of which is contained along with other substances in the dye indigo and which can be produced synthetically.
Origin
1705-15
Related forms
indigo-blue, adjective
Examples from the web for indigo blue
  • Guest rooms contain exposed brick, which makes the indigo blue colors and white deco-style lacquered furniture pop.
  • Recently killed specimens turn a bright indigo blue.
  • In late summer the leaves have died back leaving the stem upright with a cluster of indigo blue berries at the tip.
British Dictionary definitions for indigo blue

indigo blue

noun, adjective (indigo-blue when prenominal)
1.
the full name for indigo (sense 1), indigo (sense 3)