Examples:
cartography
card
archaeology
archetype
monarchy
legal
loyal
purse
personal
cinema
kinase
car
carpenter
hippopotamus
Mesopotamia
dative
data
date
...
Welsh
doeth
←
Proto-Brythonic
*doɨθ
(inherited)
←
Latin
doctus
(borrowed)
←
Middle Welsh
doeth
(inherited)
→
Welsh
doethair
(affix)