Examples:
cartography
card
archaeology
archetype
monarchy
legal
loyal
purse
personal
cinema
kinase
car
carpenter
hippopotamus
Mesopotamia
dative
data
date
...
Old Portuguese
seu
←
Latin
suus
(inherited)
→
Fala
sei
(inherited)
→
Galician
seu
(inherited)
→
Indo-Portuguese
su
(derived)
→
Portuguese
seu
(inherited)