Examples: cartography card archaeology archetype monarchy legal loyal purse personal cinema kinase car carpenter hippopotamus Mesopotamia dative data date
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Dutch droef
German trüb (cognate)
Middle Dutch droeve (inherited)
Middle Dutch droue (mention)
English droff (cognate)
Proto-Germanic *drōbuz (inherited)
Proto-West Germanic *drōbī (inherited)
Dutch droefenis (link)
Dutch droefgeestig (link)
Dutch droefheid (link)
Dutch droevig (link)
Dutch droeven (link)
Old Dutch *drōvi (inherited)
Old Dutch *druovi (mention)

English trub (cognate)
English droff (cognate)
German trüb (cognate)
Luxembourgish dréif (cognate)
Dutch droevig (suffix)
Dutch droefheid (suffix)
Dutch droefenis (affix)
Dutch droefgeestig (affix)