Examples:
cartography
card
archaeology
archetype
monarchy
legal
loyal
purse
personal
cinema
kinase
car
carpenter
hippopotamus
Mesopotamia
dative
data
date
...
Breton
heol
→
Welsh
haul
(cognate)
→
Irish
súil
(cognate)
→
Scottish Gaelic
sùil
(cognate)
→
Manx
sooill
(cognate)
→
Cornish
howl
(cognate)
→
Old Irish
súil
(cognate)