Definition of polycyclic in English:



  • 1Relating to or resulting from many cycles.

    • ‘In a screen for defective courtship songs, the nonA diss mutant was identified by its abnormal pulse songs, which become increasingly polycyclic and very high in amplitude during a song burst.’
    • ‘Interestingly, the latter's mutant song phenotype shows similarities to the wild-type songs of the D. virilis group of species, which has song pulses that are more polycyclic than those of D. melanogaster.’
    1. 1.1Chemistry (of an organic compound) having several rings of atoms in the molecule.
      • ‘Church air was found to be considerably higher in carcinogenic polycyclic hydrocarbons than air beside roads travelled by 45,000 vehicles daily.’
      • ‘The respirable portion of particulates can include acid condensates, sulfates, nitrates, and organic compounds (e.g., polycyclic aromatic hydrocarbons).’
      • ‘Hypericin, a polycyclic quinone obtained from plants of the genus Hypericum, has been shown to be a promising photosensitizer.’
      • ‘The molecules, called polycyclic aromatic hydrocarbons, are common in interstellar space, and many believe they were among the raw materials for life.’
      • ‘Chronic exposure to polycyclic aromatic compounds in dusts produced at the plant was suggested as a possible factor in the disease excesses.’
    2. 1.2Geology (of a landform or deposit) having undergone two or more cycles of erosion and deposition.
      • ‘Some structural, petrological and isotopic evidence suggests multi-stage and possibly polycyclic metamorphic evolution of the granulites of the Eastern Ghats belt.’
      • ‘The pervasively and multiply deformed polycyclic high-grade metamorphic rocks make it difficult to reconstruct the original evolutionary history of the Mozambique belt.’
      • ‘Chert fragments are likely to be polycyclic but originally derived from obducted deep-sea strata.’
      • ‘Rounded grains have occasionally been observed in thin section which, together with the very mature suite of heavy minerals present, indicates that at least some of the Manx Group detritus is polycyclic.’