Examples:
cartography
card
archaeology
archetype
monarchy
legal
loyal
purse
personal
cinema
kinase
car
carpenter
hippopotamus
Mesopotamia
dative
data
date
...
Proto-Celtic
*ognos
→
Breton
oan
(inherited)
→
Irish
uan
(inherited)
→
Scottish Gaelic
uan
(inherited)
→
Cornish
on
(inherited)
→
Cornish
ôn
(inherited)