köken: From Middle High German daȥ, from Old High German daȥ, from Proto-Germanic *þat. Compare Silesian East Central German doas, Dutch dat, English that. Doublet of dass. Distinction from dass is purely orthographical convention.
Suffix for definite form singular of common gender nouns which end in a consonant, e.g. fisk (“fish”) + -en → fisken (“the fish”); see also -n. · Definite plural suffix for certain nouns; see also -na. · gäss (“geese”) + -en → gässen (“the geese”)
köken: From forms of Old Norse hinn (demonstrative pronoun), suffixed to the end of the noun stem. From Old Norse -inn, -in, from Proto-Germanic *jainaz, from Proto-Indo-European *i-.