Examples:
cartography
card
archaeology
archetype
monarchy
legal
loyal
purse
personal
cinema
kinase
car
carpenter
hippopotamus
Mesopotamia
dative
data
date
...
Old Saxon
ek
←
Proto-Germanic
*aiks
(inherited)
←
Proto-West Germanic
*aik
(inherited)
←
Proto-Indo-European
*h₂eyǵ-
(root)