Examples:
cartography
card
archaeology
archetype
monarchy
legal
loyal
purse
personal
cinema
kinase
car
carpenter
hippopotamus
Mesopotamia
dative
data
date
...
Portuguese
contigo
←
Latin
cum
(derived)
←
Latin
tēcum
(mention)
←
Old Portuguese
contigo
(derived)
←
Old Portuguese
tigo
(mention)