Examples:
cartography
card
archaeology
archetype
monarchy
legal
loyal
purse
personal
cinema
kinase
car
carpenter
hippopotamus
Mesopotamia
dative
data
date
...
Welsh
maidd
←
Proto-Brythonic
*meið
(inherited)
←
Proto-Celtic
*mezgos
(derived)
←
Welsh
ceuled a maidd
(link)
→
English
mither
(mention)
→
French
mégot
(cognate)