The personal name Rudko, along with its variant Rud'ko, could have originated through the substantive suffix -ko from the anthropobase Rud-, which is linked to the color meaning 'reddish'. However, it could also have arisen from a truncation-suffixational method based on ancient Slavic two-root names such as Rudomysl, Rudomir, and Rudoslav. The Ukrainian personal name Rudko appears in written records as early as the 16th century. For example, in 1565, names such as Rudko Mołotiło and Rudko Warkołup are mentioned. There are also records of similarly sounding surnames from 1565, such as Markъ Rudko from the city of Bar, and Ivanъ Rud'ka, a Lviv Orthodox priest from 1590. The name of a Zaporizhian Cossack from the Bratslav Regiment is noted in 1649 as Rudko (without a surname). In the 17th century and later, the lexeme Rudkov among Ukrainians serves only as a surname. For instance, in 1649, Uman Regiment Cossacks Danilo Rudko and Yurko Rudch'enko are mentioned. In Poland, the names Rudko and Rudek can be traced back to the 14th century. For example, in 1375: Rudconede Strachon; in 1416: Petrusdictus Rudek. Patronymics were formed from the names Rudko and Rud'ko, such as in 1654: Stenka Rudch'enko, a Belarusian Cossack.
