Definition of tropism in English:



mass nounBiology
  • The turning of all or part of an organism in a particular direction in response to an external stimulus.

    • ‘This protein is embedded in and extends exterior to the viral lipid membrane and is primarily responsible for host cell receptor binding and host cell tropism.’
    • ‘It has a wide cell tropism and remains extra-chromosomal, therefore minimising the risk of insertional mutagenesis.’
    • ‘An envelope glycoprotein on the surface is thought to be responsible for mediating viral entry into cells, tissue tropism, and host range.’
    • ‘Clearly, such a rise in genetic diversity may also have important phenotypic implications, such as the emergence of viruses with altered antigenicity, virulence, or tissue tropism.’
    • ‘Our data demonstrate that factors in addition to the amount of PrP expressed determine the tropism of prions for certain tissues.’


Late 19th century: from Greek tropos ‘turning’ (from trepein ‘to turn’) + -ism.