Examples:
cartography
card
archaeology
archetype
monarchy
legal
loyal
purse
personal
cinema
kinase
car
carpenter
hippopotamus
Mesopotamia
dative
data
date
...
Proto-Celtic
*altos
→
Breton
aod
(inherited)
→
Welsh
allt
(inherited)
→
Irish
ailt
(inherited)
→
Cornish
als
(inherited)