Examples:
cartography
card
archaeology
archetype
monarchy
legal
loyal
purse
personal
cinema
kinase
car
carpenter
hippopotamus
Mesopotamia
dative
data
date
...
Cornish
kegin
←
Breton
kegin
(cognate)
←
Proto-Brythonic
*kėgin
(inherited)
←
Welsh
cegin
(cognate)
←
Latin
coquīna
(borrowed)
→
Breton
kegin
(cognate)
→
Welsh
cegin
(cognate)