cyanin / cyanine [ˈsəiənɪn]
cyanin – n. – a violet crystalline anthocyanin pigment, C27H30O16, found especially in the petals of the rose, cornflower and dahlia; cyanidin 3,5-diglucoside
cyanine – n. – 1. cyanine dye: any of a large class of unstable dyes that are important in photography for sensitivising film to light from the green, yellow, red and infrared regions of the spectrum and that are characterized by a structure containing two heterocyclic rings derived from quinoline or a related base (as benzothiazole) and typically joined by one or more carbon atoms – see carbocyanine; 2. any of a class of cyanine dyes in which the two heterocyclic rings are joined by only one carbon atom (as in =CH¯), specifically, any such dye containing two quinoline rings – called also mon-methine, simple cyanine; 3 also cyanine blue