Examples: cartography card archaeology archetype monarchy legal loyal purse personal cinema kinase car carpenter hippopotamus Mesopotamia dative data date
...
Old Irish -ad
← Proto-Celtic *-tus (derived)
← Proto-Celtic (mention)
← Proto-Celtic (mention)
← Proto-Celtic (mention)
← Proto-Celtic (mention)
← Proto-Celtic *-to (derived)
← Proto-Celtic (mention)
← Proto-Celtic (mention)
← Proto-Celtic (mention)
← Proto-Celtic (mention)

→ Irish -adh (inherited)
→ Irish -adh (inherited)
→ Irish -adh (inherited)
→ Manx -ey (inherited)
→ Old Irish cloud (affix)
→ Old Irish peccad (affix)
→ Old Irish adrad (affix)
→ Old Irish cúrsachad (affix)
→ Old Irish coíniud (affix)
→ Old Irish díbirciud (affix)
→ Old Irish cuitbiud (affix)
→ Old Irish comét (affix)
→ Old Irish foít (affix)
→ Old Irish coímchloud (affix)
→ Old Irish tochuiriud (affix)