Examples:
cartography
card
archaeology
archetype
monarchy
legal
loyal
purse
personal
cinema
kinase
car
carpenter
hippopotamus
Mesopotamia
dative
data
date
...
Old Saxon
ak
←
Old English
ac
(cognate)
←
Proto-Germanic
*ak
(inherited)
←
Old High German
oh
(cognate)
←
Gothic
𐌰𐌺
(cognate)