Examples:
cartography
card
archaeology
archetype
monarchy
legal
loyal
purse
personal
cinema
kinase
car
carpenter
hippopotamus
Mesopotamia
dative
data
date
...
Proto-Slavic
*pětьlъ
→
Bulgarian
петел
(inherited)
→
Old Church Slavonic
пѣтлъ
(inherited)
→
Macedonian
петел
(inherited)
→
Serbo-Croatian
pijetao
(derived)
→
Serbo-Croatian
petao
(derived)
→
Slovene
petel
(inherited)