Examples: cartography card archaeology archetype monarchy legal loyal purse personal cinema kinase car carpenter hippopotamus Mesopotamia dative data date
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Old Church Slavonic оу
Proto-Slavic *u (inherited)

Old Church Slavonic оубити (prefix)
Old Church Slavonic оужасъ (prefix)
Old Church Slavonic оутварь (prefix)
Old Church Slavonic оузьрѣти (prefix)
Old Church Slavonic оумꙑслити (prefix)
Old Church Slavonic оупити (prefix)
Old Church Slavonic оурокъ (prefix)
Old Church Slavonic оуставъ (prefix)
Old Church Slavonic оулоучити (prefix)
Old Church Slavonic оупъвати (prefix)
Old Church Slavonic оустроити (prefix)
Old Church Slavonic оубо (compound)
Old Church Slavonic оугобьзити (prefix)
Armenian ու (cognate)