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