Examples:
cartography
card
archaeology
archetype
monarchy
legal
loyal
purse
personal
cinema
kinase
car
carpenter
hippopotamus
Mesopotamia
dative
data
date
...
Breton
nav
←
Proto-Brythonic
*naw
(inherited)
←
Proto-Celtic
*nawan
(inherited)
←
Proto-Indo-European
*h₁néwn̥
(inherited)
→
Breton
naontek
(compound)
→
Irish
naoi
(cognate)