Examples: cartography card archaeology archetype monarchy legal loyal purse personal cinema kinase car carpenter hippopotamus Mesopotamia dative data date
...
Galician rego
← Proto-Celtic *ɸrikā (derived)
← Latin rigō (derived)
← Old Breton rec (cognate)

→ Galician regato (suffix)
→ Galician regueiro (suffix)
→ Galician derregar (prefix)
→ Galician regueira (suffix)
→ Portuguese rego (cognate)