Examples:
cartography
card
archaeology
archetype
monarchy
legal
loyal
purse
personal
cinema
kinase
car
carpenter
hippopotamus
Mesopotamia
dative
data
date
...
Irish
leathar
←
Proto-Celtic
*letrom
(inherited)
←
Welsh
lledr
(cognate)
←
Old Irish
lethar
(inherited)
→
Old English
leþer
(cognate)
→
Irish
úrleathar
(affix)