Examples:
cartography
card
archaeology
archetype
monarchy
legal
loyal
purse
personal
cinema
kinase
car
carpenter
hippopotamus
Mesopotamia
dative
data
date
...
Old Portuguese
ceo
←
Old French
ciel
(cognate)
←
Latin
caelum
(inherited)
←
Old Spanish
cielo
(cognate)
←
Old Occitan
cel
(cognate)
→
Galician
ceo
(inherited)
→
Portuguese
cio
(mention)
→
Portuguese
céu
(inherited)