Examples:
cartography
card
archaeology
archetype
monarchy
legal
loyal
purse
personal
cinema
kinase
car
carpenter
hippopotamus
Mesopotamia
dative
data
date
...
Cornish
du
←
Proto-Brythonic
*duβ
(inherited)
←
Proto-Celtic
*dubus
(inherited)
←
Proto-Indo-European
*dʰewbʰ-
(root)
←
Proto-Indo-European
*dʰewbʰ-
(derived)
→
Scottish Gaelic
dubh
(mention)
→
Cornish
mor du
(affix)