Examples:
cartography
card
archaeology
archetype
monarchy
legal
loyal
purse
personal
cinema
kinase
car
carpenter
hippopotamus
Mesopotamia
dative
data
date
...
Irish
bothóg
←
Irish
both
(affix)
←
Irish
-óg
(affix)
←
Proto-Indo-European
*bʰuH-
(root)