Examples:
cartography
card
archaeology
archetype
monarchy
legal
loyal
purse
personal
cinema
kinase
car
carpenter
hippopotamus
Mesopotamia
dative
data
date
...
Breton
prenestr
←
Welsh
ffenestr
(cognate)
←
Old French
fenestre
(borrowed)
←
Cornish
fenester
(cognate)
←
Latin
fenestra
(borrowed)
→
Breton
prenestroù
(suffix)
→
Welsh
ffenestr
(cognate)