Examples: cartography card archaeology archetype monarchy legal loyal purse personal cinema kinase car carpenter hippopotamus Mesopotamia dative data date
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Old Irish tét
Proto-Celtic *tantā (inherited)
Welsh tant (cognate)
Proto-Indo-European *ten- (root)
Proto-Indo-European *ten- (derived)
Old Irish tétach (link)
Old Irish tétaire (link)
Old Irish tétán (link)

Irish téad (inherited)
Manx tead (inherited)
Icelandic þenja (cognate)