Examples:
cartography
card
archaeology
archetype
monarchy
legal
loyal
purse
personal
cinema
kinase
car
carpenter
hippopotamus
Mesopotamia
dative
data
date
...
Cornish
mynnes
←
Breton
mennout
(cognate)
←
Welsh
mynnu
(cognate)
←
Old Cornish
*mynnet
(inherited)
→
Welsh
mynnu
(cognate)