Examples:
cartography
card
archaeology
archetype
monarchy
legal
loyal
purse
personal
cinema
kinase
car
carpenter
hippopotamus
Mesopotamia
dative
data
date
...
Irish
cacht
←
Proto-Celtic
*kaxtos
(inherited)
←
Proto-Indo-European
*kh₂ptós
(inherited)
←
Old Irish
cacht
(inherited)
→
French
chétif
(cognate)