Examples: cartography card archaeology archetype monarchy legal loyal purse personal cinema kinase car carpenter hippopotamus Mesopotamia dative data date
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Breton gast
Proto-Brythonic *gwėɣin (cognate)
Proto-Celtic *gasliyā (derived)
Proto-Celtic *gas (mention)
French gouine (cognate)
Old Irish gast (borrowed)

Breton gasted (suffix)
Breton gastoù (suffix)