Syllable division derived from spelling — this word is not in the pronouncing dictionary, so no phonetic transcription is shown rather than a guessed one.
heterocyclic is a noun and adjective meaning "a compound containing a heterocyclic ring". It carries 2 recorded senses.
a compound containing a heterocyclic ring
containing a closed ring of atoms of which at least one is not a carbon atom
Forms marked · are formed by the regular rule rather than recorded in the source data. English keeps a few hundred irregulars and the rest follow the pattern, so the rule is right far more often than not — but it is a rule, and the mark says so.
Definitions, synonyms and semantic relations for heterocyclic come from Princeton University’s WordNet. Commonness is measured against a corpus of everyday English. Full sources and licences.