Lithuanian Etymology From su Dievu (literally “(go) with God”).[1] Compare partial cognates Spanish adiós and French adieu. Interjection sudiẽ bye, adieu References [1]Wojciech Smoczyński (2018) “sudie”, in Lithuanian Etymological Dictionary, Berlin, Germany: Peter Lang, →DOI, →ISBN, page 612 Wikiwand - on Seamless Wikipedia browsing. On steroids.