Examples:
cartography
card
archaeology
archetype
monarchy
legal
loyal
purse
personal
cinema
kinase
car
carpenter
hippopotamus
Mesopotamia
dative
data
date
...
Middle Irish
-óc
→
Middle Irish
-ach
(doublet)
→
Middle Irish
fésóc
(affix)
→
Middle Irish
cammóc
(affix)
→
Middle Irish
fuinnseóg
(suffix)
→
Middle Irish
crannóc
(affix)