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pyrazoline

American  
[pi-raz-uh-leen, -lin, pahy-] / pɪˈræz əˌlin, -lɪn, paɪ- /

noun

Chemistry.
  1. any of the group of heterocyclic compounds containing three carbon atoms, two adjacent nitrogen atoms, and one double bond in the ring.

  2. the parent compound, C 3 H 6 N 2 .


Etymology

Origin of pyrazoline

First recorded in 1885–90; pyrazole + -ine 2