Examples: cartography card archaeology archetype monarchy legal loyal purse personal cinema kinase car carpenter hippopotamus Mesopotamia dative data date
...
Old English -ga
← Proto-Germanic *-gjô (inherited)
← Proto-Germanic *-gô (mention)
← Proto-West Germanic *-gō (inherited)

→ English dog (mention)
→ Old English docga (suffix)
→ Old English wicga (suffix)
→ Old English stacga (suffix)
→ Old English scucca (suffix)
→ Old English sceacga (suffix)