Examples:
cartography
card
archaeology
archetype
monarchy
legal
loyal
purse
personal
cinema
kinase
car
carpenter
hippopotamus
Mesopotamia
dative
data
date
...
Welsh
Sadwrn
←
Breton
Sadorn
(cognate)
←
Cornish
-
(cognate)
←
Latin
Saturnus
(borrowed)
→
Breton
Sadorn
(cognate)
→
Welsh
dydd Sadwrn
(compound)
→
Welsh
nos Sadwrn
(compound)