Examples:
cartography
card
archaeology
archetype
monarchy
legal
loyal
purse
personal
cinema
kinase
car
carpenter
hippopotamus
Mesopotamia
dative
data
date
...
Bulgarian
мрак
←
Proto-Slavic
*morkъ
(inherited)
→
Bulgarian
мрачен
(affix)
→
Bulgarian
мраченик
(affix)