Examples: cartography card archaeology archetype monarchy legal loyal purse personal cinema kinase car carpenter hippopotamus Mesopotamia dative data date
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Ukrainian взаємний
Belarusian узае́мны (cognate)
Polish wzajemny (cognate)
Russian взаи́мный (cognate)
Proto-Slavic *ѵъ (inherited)
Proto-Slavic *zajьmъ (mention)
Ukrainian -ний (affix)