Examples: cartography card archaeology archetype monarchy legal loyal purse personal cinema kinase car carpenter hippopotamus Mesopotamia dative data date
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Icelandic dökkur
German dunkel (cognate)
Faroese døkkur (cognate)
Proto-Germanic *dankwaz (derived)
Old Norse døkkr (derived)
Old Norse dǫkkr (mention)

Faroese døkkur (cognate)
Icelandic dökkbrúnn (affix)
Icelandic dökkvíðir (affix)
Icelandic dökkasef (affix)
Icelandic dökkhæra (affix)