Examples:
cartography
card
archaeology
archetype
monarchy
legal
loyal
purse
personal
cinema
kinase
car
carpenter
hippopotamus
Mesopotamia
dative
data
date
...
Old Irish
clé
←
Proto-Celtic
*kliyos
(inherited)
→
Irish
clé
(inherited)
→
Old Irish
fochlae
(mention)
→
Old Irish
fochlae
(affix)