Examples: cartography card archaeology archetype monarchy legal loyal purse personal cinema kinase car carpenter hippopotamus Mesopotamia dative data date
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Romanian un
Proto-Indo-European *óynos (inherited)
Old Latin oinos (inherited)
Proto-Italic *oinos (inherited)
Latin ūnus (inherited)

Romanian o (link)
Romanian uni (mention)
Romanian unsprezece (mention)
Romanian într-un (compound)
Romanian dintr-un (compound)
Romanian printr-un (compound)
Romanian unul (mention)
Romanian împreună (mention)
Romanian niciun (compound)
Istro-Romanian ur (cognate)
Aromanian un (cognate)