Examples:
cartography
card
archaeology
archetype
monarchy
legal
loyal
purse
personal
cinema
kinase
car
carpenter
hippopotamus
Mesopotamia
dative
data
date
...
Luxembourgish
joen
←
Proto-West Germanic
*jagōn
(inherited)
←
Old High German
jagōn
(inherited)
→
Luxembourgish
Jeeër
(suffix)