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