The name 'Tomko' is a truncated-suffix formation derived from the Slavic two-root name 'Tomsilav' or from its colloquial form 'Tomilo,' which was known among Poles, Serbs, and Croats. The name is formed using the diminutive suffix '-ko.' In Ukrainian written records, the name 'Tomko' begins to appear only from the year 1459. For example, documents mention a gentleman named Tomko from the city of Lutsk, and in 1584, Tomko Khomyts, a bailiff of Kyiv County. In 1620, there is a reference to Tomko Skrypych from the village of Novosilki. Among the Zaporizhian Cossacks in 1649, eight Cossacks were recorded with the name 'Tomko.' For instance, Cossack Tomko Lashenko from the Cherkasy regiment, Cossack Tomko Yurchenko from the Cherkasy regiment, Cossack Tomko Sobchenko from the Kropyvnyansk regiment, and Cossack Tomko Strelts from the Poltava regiment. Some of these names might be derived from the calendar name Thomas, which corresponds to Khoma.