Examples:
cartography
card
archaeology
archetype
monarchy
legal
loyal
purse
personal
cinema
kinase
car
carpenter
hippopotamus
Mesopotamia
dative
data
date
...
Proto-Celtic
*awyos
→
Manx
oe
(inherited)
→
Primitive Irish
ᚐᚃᚔ
(inherited)
→
Old Irish
úa
(inherited)