Examples:
cartography
card
archaeology
archetype
monarchy
legal
loyal
purse
personal
cinema
kinase
car
carpenter
hippopotamus
Mesopotamia
dative
data
date
...
Old French
oef
←
Proto-Indo-European
*h₂ōwyóm
(inherited)
←
Proto-Italic
*ōwom
(inherited)
←
Latin
ōvum
(inherited)
→
French
œuf
(inherited)
→
Middle French
œuf
(inherited)
→
Norman
oeu
(inherited)
→
Norman
œu
(inherited)
→
Walloon
oû
(inherited)