Examples:
cartography
card
archaeology
archetype
monarchy
legal
loyal
purse
personal
cinema
kinase
car
carpenter
hippopotamus
Mesopotamia
dative
data
date
...
Galician
marulán
←
Proto-Celtic
*māros
(derived)
←
Undetermined
*marullanus
(mention)
→
Galician
marulo
(back-formation)