Examples:
cartography
card
archaeology
archetype
monarchy
legal
loyal
purse
personal
cinema
kinase
car
carpenter
hippopotamus
Mesopotamia
dative
data
date
...
Breton
teod
←
Proto-Celtic
*tangʷāss
(inherited)
←
Welsh
tafod
(cognate)
←
Irish
teanga
(cognate)
←
Proto-Indo-European
*dn̥ǵʰwéh₂s
(inherited)