each · individually, severally, singly · one by one
köken: Lexicalization of the obsolete adverb egyen (“one by one, separately”) + -ként (essive-formal case suffix), from egy (“one”) + -en (case suffix). First attested in 1531.
köken: Etymology tree Proto-Indo-European *ís? Proto-Indo-European *h₁óynos Proto-Italic *oinos Old Latin oinos Latin ūnusder. Esperanto unu Esperanto -ope Esperanto unuope From unu (“one”) + -ope.