Examples:
cartography
card
archaeology
archetype
monarchy
legal
loyal
purse
personal
cinema
kinase
car
carpenter
hippopotamus
Mesopotamia
dative
data
date
...
Old Church Slavonic
чистъ
←
Proto-Slavic
*čistъ
(inherited)
→
Old Church Slavonic
чистость
(suffix)
→
Old Church Slavonic
чистота
(affix)