Examples:
cartography
card
archaeology
archetype
monarchy
legal
loyal
purse
personal
cinema
kinase
car
carpenter
hippopotamus
Mesopotamia
dative
data
date
...
Breton
kalc'h
←
Proto-Brythonic
*kalɣ
(inherited)
←
Proto-Celtic
*kalgā
(inherited)
→
Breton
kalc'hioù
(suffix)
→
Welsh
cala
(cognate)
→
Galician
carallo
(cognate)