Examples: cartography card archaeology archetype monarchy legal loyal purse personal cinema kinase car carpenter hippopotamus Mesopotamia dative data date
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Gaulish con-
Breton kev- (cognate)
Breton kem- (mention)
Proto-Celtic *kom- (inherited)
Welsh cyf- (cognate)
Proto-Indo-European *ḱóm (derived)
Old Irish com- (cognate)