Examples:
cartography
card
archaeology
archetype
monarchy
legal
loyal
purse
personal
cinema
kinase
car
carpenter
hippopotamus
Mesopotamia
dative
data
date
...
Irish
cúigear
←
Old Irish
cóicer
(inherited)
←
Old Irish
cóic
(mention)
←
Old Irish
fer
(mention)
→
Irish
seachtar
(mention)