Examples: cartography card archaeology archetype monarchy legal loyal purse personal cinema kinase car carpenter hippopotamus Mesopotamia dative data date
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Icelandic vetni
French hydrogène (cognate)
Ancient Greek ὕδωρ (cognate)
Icelandic vatn (mention)

Icelandic tvívetni (prefix)
Icelandic þrívetni (prefix)
Icelandic einvetni (prefix)
Icelandic ofurþungt vetni (mention)