Examples:
cartography
card
archaeology
archetype
monarchy
legal
loyal
purse
personal
cinema
kinase
car
carpenter
hippopotamus
Mesopotamia
dative
data
date
...
Corsican
cù
←
Proto-Indo-European
*ḱóm
(inherited)
←
Italian
con
(cognate)
←
Old Latin
com
(inherited)
←
Proto-Italic
*kom
(inherited)
←
Latin
cum
(inherited)
←
Romanian
cu
(cognate)