The name "Rusan" is formed using the attributive suffix -an from the adjective stem rus-, similar to other names, such as Bilan or Dovhan. The original meaning of this formation was likely "red-haired boy." The name is documented in writing since 1388 when Prince Rusan Plaksich was mentioned in the village of Luchytsia. Starting from the 17th century, the lexeme Rusan and its derivatives in Ukraine are primarily used as additional identifiers with personal names. For example, in 1604, a nobleman Jo. Ruzan is mentioned in the village of S. Vodyane, and in 1635, a subject named Lasha called Semen Pusanivskyi is referenced. In 1665, a craftsman named Csubirka alias Russzan Ricz is noted in the village of Tyushka. Patronymics such as Rusанов in 1666 and Русанович in 1671, when a monk from Lubny is mentioned, are formed from the name Rusan. Among other variants of the name, the Serbian male name Rusан and the Croatian name Rusan can also be noted. Croatian onomasticians suggest that this personal name may derive from the adjective stem rus-, which means 'reddish, red,' with the addition of the suffix -an.