Examples: cartography card archaeology archetype monarchy legal loyal purse personal cinema kinase car carpenter hippopotamus Mesopotamia dative data date
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Welsh rhy
Proto-Brythonic *rro (inherited)
Proto-Celtic *ɸro (inherited)
Welsh rhydd (link)
Welsh dyry (link)
Proto-Indo-European *pró (inherited)

Breton re (cognate)
Welsh rhydd (link)
Welsh rhiant (affix)
Welsh rhieni (affix)
Welsh crybwyll (affix)