Examples:
cartography
card
archaeology
archetype
monarchy
legal
loyal
purse
personal
cinema
kinase
car
carpenter
hippopotamus
Mesopotamia
dative
data
date
...
Welsh
meddu
←
Proto-Brythonic
*mėðɨd
(inherited)
←
Proto-Celtic
*medyetor
(inherited)
←
Proto-Indo-European
*med-
(root)
←
Proto-Indo-European
*med-
(derived)
←
Old Irish
midithir
(cognate)
→
Welsh
meddiant
(affix)