Examples:
cartography
card
archaeology
archetype
monarchy
legal
loyal
purse
personal
cinema
kinase
car
carpenter
hippopotamus
Mesopotamia
dative
data
date
...
Breton
fri
←
Proto-Celtic
*srognā
(derived)
←
Welsh
ffroen
(cognate)
←
Cornish
frig
(cognate)
←
Old Irish
srón
(cognate)