Examples:
cartography
card
archaeology
archetype
monarchy
legal
loyal
purse
personal
cinema
kinase
car
carpenter
hippopotamus
Mesopotamia
dative
data
date
...
Proto-Celtic
*tegus
→
Breton
tev
(inherited)
→
Welsh
tew
(inherited)
→
Irish
tiubh
(inherited)
→
Scottish Gaelic
tiugh
(inherited)
→
Manx
çhiu
(inherited)
→
Old Irish
tiug
(inherited)