Examples: cartography card archaeology archetype monarchy legal loyal purse personal cinema kinase car carpenter hippopotamus Mesopotamia dative data date
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Welsh saeth
Breton saezh (cognate)
Proto-Brythonic *saɣeθ (inherited)
Irish saighead (cognate)
Cornish seth (cognate)
Latin sagitta (derived)
Middle Welsh saeth (inherited)

Welsh saethu (suffix)