Examples:
cartography
card
archaeology
archetype
monarchy
legal
loyal
purse
personal
cinema
kinase
car
carpenter
hippopotamus
Mesopotamia
dative
data
date
...
Czech
prosinec
←
Proto-Slavic
*prosìnьcь
(inherited)
→
Czech
prosincový
(suffix)
→
Serbo-Croatian
prosinac
(cognate)
→
Old Polish
prosień
(cognate)
→
Old Polish
prosiniec
(cognate)