Examples: cartography card archaeology archetype monarchy legal loyal purse personal cinema kinase car carpenter hippopotamus Mesopotamia dative data date
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Breton avu
Proto-Brythonic *aβʉ (inherited)
Proto-Celtic *awV- (inherited)
Welsh afu (cognate)
Cornish avi (cognate)
Middle Irish áe (cognate)
Middle Breton auu (inherited)

Welsh afu (cognate)