Examples:
cartography
card
archaeology
archetype
monarchy
legal
loyal
purse
personal
cinema
kinase
car
carpenter
hippopotamus
Mesopotamia
dative
data
date
...
Irish
beithíoch
←
Scottish Gaelic
beithir
(cognate)
←
Old Irish
bethadach
(inherited)
→
Irish
ainbheithíoch
(affix)
→
Scottish Gaelic
beathach
(cognate)