Examples:
cartography
card
archaeology
archetype
monarchy
legal
loyal
purse
personal
cinema
kinase
car
carpenter
hippopotamus
Mesopotamia
dative
data
date
...
Breton
traezh
←
Proto-Brythonic
*traɨθ
(inherited)
←
Proto-Celtic
*traxtus
(inherited)
←
Welsh
traeth
(cognate)
←
Irish
trácht
(cognate)
←
Cornish
treth
(cognate)
←
Middle Breton
traez
(inherited)
→
Welsh
traeth
(cognate)
→
Cornish
treth
(cognate)