Examples:
cartography
card
archaeology
archetype
monarchy
legal
loyal
purse
personal
cinema
kinase
car
carpenter
hippopotamus
Mesopotamia
dative
data
date
...
Cornish
Est
←
Breton
Eost
(cognate)
←
Welsh
Awst
(cognate)
←
Latin
Augustus
(borrowed)
→
Breton
Eost
(cognate)