Examples:
cartography
card
archaeology
archetype
monarchy
legal
loyal
purse
personal
cinema
kinase
car
carpenter
hippopotamus
Mesopotamia
dative
data
date
...
Proto-Indo-European
*h₂eǵro-
→
Irish
ár
(inherited)
→
Scottish Gaelic
àr
(derived)
→
Manx
haar
(derived)
→
Old Irish
ár
(inherited)