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cycloaddition

American  
[sahy-kloh-uh-dish-uhn, sik-loh-] / ˌsaɪ kloʊ əˈdɪʃ ən, ˌsɪk loʊ- /

noun

Chemistry.
  1. the formation of a cyclic compound by the addition reaction of unsaturated molecules.


Etymology

Origin of cycloaddition

First recorded in 1960–65; cyclo- + addition