Examples:
cartography
card
archaeology
archetype
monarchy
legal
loyal
purse
personal
cinema
kinase
car
carpenter
hippopotamus
Mesopotamia
dative
data
date
...
Czech
řídký
←
Proto-Slavic
*rědъkъ
(inherited)
→
Czech
řídkost
(affix)
→
Welsh
rhwydd
(cognate)