A number of Lithuanian surnames evolved from the ancient pre-Christian Lithuanian personal names, such as Budrys, Girdenis, Tylenis, Vilkas, Amantas, Bukantas, Rimgaila, Vizgirda, Tarvydas.
[2][3][4] Sometimes the order of these stems may reverse, e.g., Norvaišas vs. Vaišnoras, Tautvydas vs. Vytautas.
Some two-stemmed names have a clear etymology, arising from nicknames, such as Baltakis = Balt-akys = "White eyes".
Alfred Senn suggects that such transparent names are less ancient development, while those with non-evident etymology originate from the Indo-European pra-language.
[5] A two-stemmed name may be further compounded into a patronymic cognomen/surname: Algirdas—Algirdaitis (son of Algirdas; see Lithuanian names of Vladimir Olgerdovich, Andrei of Polotsk, Dmitry of Bryansk), Žygimantas—Žygimantaitis.