polymethine dye


Definition of polymethine dye

: any of a class of dyes (as cyanines or merocyanines) characterized by a resonance structure containing a conjugated chain of carbon atoms that is at least in part an open chain [as in −CH(=CH−CH)n=] attached to two polar atoms (as two amino nitrogen atoms either one of which is considered to be positively charged)

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to wander slowly or to speak indistinctly

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