Examples: cartography card archaeology archetype monarchy legal loyal purse personal cinema kinase car carpenter hippopotamus Mesopotamia dative data date
...
Irish cas
← Proto-Celtic *kassos (inherited)
← Old Irish cass (inherited)

→ Gaulish cassanos (cognate)
→ Irish casadh (affix)
→ Irish caschlár (affix)
→ Irish caschiorcal (affix)
→ Irish castóir (affix)
→ Irish barrchas (affix)