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adj. External to a chemical ring structure: an exocyclic double bond.

adj. (of a cyclic compound) not forming part of, or not attached to the ring

Pertaining to the Exocyclica; having an eccentric anus, as a clypeastroid or spatangoid seaurchin.

"Formaldehyde also affects nucleic acids by forming adducts with exocyclic nitrogen atoms in nucleotides"

acronyms    carbon-carbon    piped-in    hyperbaric    break-point