Examples:
cartography
card
archaeology
archetype
monarchy
legal
loyal
purse
personal
cinema
kinase
car
carpenter
hippopotamus
Mesopotamia
dative
data
date
...
Latin
opinor
←
Proto-Indo-European
*op-
(derived)
←
Latin
*opīnus
(mention)
←
Latin
inopīnus
(mention)
←
Latin
necopīnus
(mention)
←
Latin
optō
(mention)