Examples: cartography card archaeology archetype monarchy legal loyal purse personal cinema kinase car carpenter hippopotamus Mesopotamia dative data date
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Icelandic átján
Danish atten (cognate)
German achtzehn (cognate)
English eighteen (cognate)
Proto-Germanic *ahtōutehun (derived)
Old Norse átján (derived)
Swedish arton (cognate)

Westrobothnian atan (cognate)
Icelandic einn af átján (mention)