iso·mer·ic \| ̷ ̷ ̷ ̷|merik\adjective Etymology: International Scientific Vocabulary isomer- (from Greek isomerēs equally divided, from is- + meros part, share) + -ic — more at merit : of, relating to, or exhibiting isomerism < butane and isobutane are isomeric compounds > < the thiocyanate and isothiocyanate radicals are isomeric > • iso·mer·i·cal·ly\-rə̇k(ə)lē\adverb