Examples:
cartography
card
archaeology
archetype
monarchy
legal
loyal
purse
personal
cinema
kinase
car
carpenter
hippopotamus
Mesopotamia
dative
data
date
...
Proto-Celtic
*wan-inyo-
→
Breton
gwenan
(inherited)
→
Welsh
gwenyn
(inherited)
→
Cornish
gwenen
(inherited)