Examples:
cartography
card
archaeology
archetype
monarchy
legal
loyal
purse
personal
cinema
kinase
car
carpenter
hippopotamus
Mesopotamia
dative
data
date
...
Bulgarian
ручей
←
Bulgarian
руча́
(affix)
←
Bulgarian
-ей
(affix)
←
Proto-Slavic
*ručьjь
(inherited)