Examples:
cartography
card
archaeology
archetype
monarchy
legal
loyal
purse
personal
cinema
kinase
car
carpenter
hippopotamus
Mesopotamia
dative
data
date
...
Welsh
-did
←
Proto-Celtic
*-tūss
(derived)
←
Proto-Germanic
*-dūþiz
(cognate)
←
Proto-Indo-European
*-tuHts
(derived)
←
Latin
-tus
(cognate)
←
Middle Welsh
-dit
(inherited)
→
Welsh
digalondid
(affix)
→
Welsh
-didau
(compound)