Examples:
cartography
card
archaeology
archetype
monarchy
legal
loyal
purse
personal
cinema
kinase
car
carpenter
hippopotamus
Mesopotamia
dative
data
date
...
Cornish
karrek
←
Breton
karreg
(cognate)
←
Proto-Celtic
*karrikā
(inherited)
←
Welsh
carreg
(cognate)
←
Old Irish
carrac
(cognate)
→
Welsh
carreg
(cognate)
→
Basque
harri
(cognate)