ˈsīəˌnēn, -_nə̇n noun
( -s )
Etymology: International Scientific Vocabulary cyan- + -ine
1. or cyanine dye : any of a large class of usually unstable dyes that are important in photography for sensitizing 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 monomethine, simple cyanine
3. also cy·a·nin -_nə̇n or cyanine blue
a. : a blue cyanine dye (sense 2) C 29 H 35 IN 2 obtained from quinoline, lepidine, and isoamyl iodide; 1,1′-di-isoamyl-4,4′-cyanine iodide — called also quinoline blue
b. : a homologue (as the diethyl compound) of this dye — called also quinoline blue