Examples:
cartography
card
archaeology
archetype
monarchy
legal
loyal
purse
personal
cinema
kinase
car
carpenter
hippopotamus
Mesopotamia
dative
data
date
...
Breton
ster
←
Breton
stered
(link)
←
Proto-Brythonic
*ster
(inherited)
←
Proto-Celtic
*sterā
(inherited)
←
Proto-Indo-European
*h₂stḗr
(inherited)
→
Breton
stered
(suffix)