Examples:
cartography
card
archaeology
archetype
monarchy
legal
loyal
purse
personal
cinema
kinase
car
carpenter
hippopotamus
Mesopotamia
dative
data
date
...
Danish
ir
←
Proto-Germanic
*aiz
(inherited)
←
Old Danish
eer
(inherited)
←
Old Norse
eir
(derived)
→
Icelandic
eir
(cognate)
→
Norwegian Nynorsk
eir
(cognate)