Examples:
cartography
card
archaeology
archetype
monarchy
legal
loyal
purse
personal
cinema
kinase
car
carpenter
hippopotamus
Mesopotamia
dative
data
date
...
English
suero
←
English
serum
(doublet)
←
Spanish
suero
(borrowed)
←
Proto-Indo-European
*ser- (flow)
(root)
→
English
serum
(doublet)