Examples:
cartography
card
archaeology
archetype
monarchy
legal
loyal
purse
personal
cinema
kinase
car
carpenter
hippopotamus
Mesopotamia
dative
data
date
...
Ukrainian
синочок
←
Belarusian
сыно́чак
(cognate)
←
Polish
syneczek
(cognate)
←
Russian
сыно́чек
(cognate)
←
Ukrainian
сино́к
(affix)
←
Ukrainian
-о́к
(affix)