Examples:
cartography
card
archaeology
archetype
monarchy
legal
loyal
purse
personal
cinema
kinase
car
carpenter
hippopotamus
Mesopotamia
dative
data
date
...
Irish
Peadar
←
Ancient Greek
Πέτρος
(derived)
←
Ancient Greek
πέτρος
(mention)
←
Latin
Petrus
(derived)
←
Old Irish
Petur
(inherited)