noun
Etymology: after Queen Victoria
1. usually capitalized V & often capitalized B : any of several basic dyes derived from diphenyl-naphthyl-methane that dye wool and silk royal blue and are used also as biological stains and organic pigments: as
a. or victoria blue B : a dye made from Michler's ketone and N -phenyl-alpha-naphthylamine — see dye table I (under Basic Blue 26, Pigment Blue 2, Solvent Blue 4 )
b. or victoria blue R : a dye made from Michler's ketone and N -ethyl-alpha-naphthylamine — see dye table I (under Basic Blue 11, Solvent Blue 6 )
c. : victoria pure blue B
2. often capitalized V : a strong blue that is redder and duller than Sèvres, cerulean blue (sense 1b), or cyanine blue (sense 1a)