The name Semak is an ancient Slavic masculine name given to a son born as the seventh child in the family. It is less likely that the name is derived from some Slavic composite, such as Semibor, Semirad, Semislav, Siemimysl, Semignev..., where the root "sem" is associated with the meaning of "semja" — 'family, household'. Information about the name Semak has been recorded in historical documents from the 16th century. For example, in 1565 there are records of Siemak Haniow, Semak Kunatowski, and Syemak Araszimowicz. Between 1648 and 1651, the name Semak Tymkow was recorded. In Transcarpathia, the anthroponym Semak has been known since the 15th century, but it was mainly used as an additional designation of a person alongside their name.Additionally, in the years 1443 and 1449, citizens Damiani Zemak and Ladislai Zemak are mentioned. In 1649, a well-known Cossack from the Uman regiment, Ivan Siomak, is documented, and in 1720, a serf named Joseph Semak from the village of Horinchovo is noted. In Poland, the anthroponym Siemak has been recorded since the 13th century.
