Examples:
cartography
card
archaeology
archetype
monarchy
legal
loyal
purse
personal
cinema
kinase
car
carpenter
hippopotamus
Mesopotamia
dative
data
date
...
Cornish
Me
←
Breton
Mae
(cognate)
←
Welsh
Mai
(cognate)
←
Latin
māius
(derived)
→
Breton
Mae
(cognate)