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

→ Irish tráth (inherited)
→ Scottish Gaelic tràth (inherited)
→ Scottish Gaelic mochthrath (mention)
→ Manx traa (inherited)
→ Manx moghrey (mention)
→ Old Irish úar (link)
→ Old Irish tráthamail (suffix)
→ Old Irish tráthach (affix)