Examples:
cartography
card
archaeology
archetype
monarchy
legal
loyal
purse
personal
cinema
kinase
car
carpenter
hippopotamus
Mesopotamia
dative
data
date
...
Aromanian
optu
←
Proto-Indo-European
*oḱtṓw
(inherited)
←
Latin
octō
(inherited)
←
Romanian
opt
(cognate)
→
Aromanian
uptimi
(suffix)