Examples:
cartography
card
archaeology
archetype
monarchy
legal
loyal
purse
personal
cinema
kinase
car
carpenter
hippopotamus
Mesopotamia
dative
data
date
...
Irish
uillinn
←
Proto-Celtic
*olīnā
(inherited)
←
Old Irish
uilen
(inherited)
→
Welsh
elin
(cognate)
→
Irish
frithuillinn
(affix)
→
Irish
dronuilleog
(affix)
→
Manx
uillin
(cognate)
→
Cornish
elin
(cognate)