Examples:
cartography
card
archaeology
archetype
monarchy
legal
loyal
purse
personal
cinema
kinase
car
carpenter
hippopotamus
Mesopotamia
dative
data
date
...
Polish
rój
←
Proto-Slavic
*rojь
(inherited)
→
Lower Sorbian
roj
(cognate)
→
Polish
rójka
(affix)
→
Polish
rojny
(affix)