Examples: cartography card archaeology archetype monarchy legal loyal purse personal cinema kinase car carpenter hippopotamus Mesopotamia dative data date
...
Old Irish eidenn

→ Irish eidheann (inherited)
→ Irish eidhneán (mention)
→ Irish eidhneach (mention)
→ Irish eidhneánach (mention)
→ Scottish Gaelic eidheann (inherited)