The personal names Chayko and Chayka, according to S. Ilcheva, originate from the ancient verb "chayaty," which means 'to wait' or 'to expect' (Ilcheva 354). According to Y. Svoboda and M. Hrvkovych, the name Chayka is not the name of a known bird but belongs to deformed Old Slavic names with the verbal component "chayaty" 'to wait,' similar to names like Milochay, Radochay, and Nechay (Svoboda 731; Hrvkovych 209). The name Chayka, like Chayko, began to be recorded in Ukraine from the 15th century. For example, in 1437, the name Ivan Tsayko was recorded (AGZ XI 104); in 1552 - Chayka (OKZ 103); in 1552 - Chayka, a Kyiv boyar (Arch YUZR VII/1 104); in 1649 - Cossack Bohdan Chayka from the Poltava Regiment (RVZ 407) and Cossack Kostiuk Chayka from the Kropyvnyansky Regiment (RVZ 355); in 1666 - Roman Chayka (PK 221); in 1681 - serf Istvan Chayka from the village of Hanychi in Tyachiv region (Belay 147). It is also worth noting the patronymics from 1565 Czayczyn (LSH 135); in 1638 - Jan Chaykovych (Arch YUZR III/1 374); in 1649 - Cossack Vasyl Chaykovskyi from the Uman Regiment (RVZ 227); in 1715 - serf Mati Chayka from the village of Hanychi (Belay 147).In Ukrainian territories, there are numerous ancient toponyms that contain the anthropo-root "chai-," for example, Pochayiv, Pochata, and Pochayevychi. In Poland, the anthroponyms Czayca and Czaja have been recorded since the 14th-15th centuries (SSNO I 397).