Examples:
cartography
card
archaeology
archetype
monarchy
legal
loyal
purse
personal
cinema
kinase
car
carpenter
hippopotamus
Mesopotamia
dative
data
date
...
Old Frisian
en
←
Old English
ān
(cognate)
←
Proto-West Germanic
*ain
(inherited)
←
Old Saxon
ēn
(cognate)
→
Old Norse
einn
(cognate)