Definition of pyrrole in English:


Pronunciation /ˈpirōl/ /ˈpɪroʊl/


  • A weakly basic sweet-smelling liquid compound present in bone oil and coal tar.

    A heteroaromatic compound; chemical formula: C₄H₄NH

    ‘This step is followed by polymerising pyrrole vapours to produce a foam composite.’
    • ‘The free-base form of such porphyrins contains two pyrrole nitrogens.’
    • ‘The Netropsin ligand consists of a guanidinium, two pyrrole, and a propylamidinium part.’
    • ‘This would make this particular pyrrole group unequivalent with the others.’


Mid 19th century from Greek purrhos ‘reddish’ + Latin oleum ‘oil’.