Definition of thymidine in US English:



  • A crystalline nucleoside present in DNA, consisting of thymine linked to deoxyribose.

    • ‘Methionine synthase inhibition causes folate trapping and a reduction in the amount of folate available for thymidine synthesis as described above.’
    • ‘A DNA substrate containing a thymidine kinase gene fused to a neomycin-resistance gene was stably integrated into cells.’
    • ‘However, as indicated above, the salvage pathway to thymidine nucleotide synthesis is especially important in the preparation for cell division.’
    • ‘Both of these enzymes are involved in thymidine nucleotide biosynthesis.’
    • ‘For gene therapy based on the introduction of the herpes simplex virus thymidine kinase gene, the bystander effect depends on cell to cell contact and the presence of gap junctions.’


Early 20th century: from thymine + -ide + -ine.