Examples:
cartography
card
archaeology
archetype
monarchy
legal
loyal
purse
personal
cinema
kinase
car
carpenter
hippopotamus
Mesopotamia
dative
data
date
...
Bulgarian
кръг
←
Proto-Slavic
*krǫgъ
(inherited)
→
Bulgarian
-ом
(link)
→
Bulgarian
кръжок
(affix)