Examples:
cartography
card
archaeology
archetype
monarchy
legal
loyal
purse
personal
cinema
kinase
car
carpenter
hippopotamus
Mesopotamia
dative
data
date
...
Gaulish
mapos
←
Proto-Celtic
*makʷos
(inherited)
←
Welsh
mab
(cognate)
←
Old Irish
macc
(cognate)
→
Irish
mac
(cognate)
→
Primitive Irish
ᚋᚐᚊᚔ
(cognate)
→
Old Irish
macc
(cognate)