Examples:
cartography
card
archaeology
archetype
monarchy
legal
loyal
purse
personal
cinema
kinase
car
carpenter
hippopotamus
Mesopotamia
dative
data
date
...
Old Irish
senmáthair
←
Old Irish
sen
(compound)
←
Old Irish
máthir
(compound)
→
Irish
seanmháthair
(inherited)
→
Scottish Gaelic
seanmhair
(inherited)